Bug 1363481 - Add the old attribute value as a parameter to Element::AfterSetAttr

Tag #1375

42 files changed, 125 insertions, 62 deletions

diff --git a/dom/html/HTMLBodyElement.cpp b/dom/html/HTMLBodyElement.cpp
index f70e203897..112d48dd15 100644
--- a/dom/html/HTMLBodyElement.cpp
+++ b/dom/html/HTMLBodyElement.cpp
@@ -307,10 +307,11 @@ HTMLBodyElement::BindToTree(nsIDocument* aDocument, nsIContent* aParent,
 nsresult
 HTMLBodyElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                               const nsAttrValue* aValue,
-                              bool aNotify)
+                              const nsAttrValue* aOldValue, bool aNotify)
 {
   nsresult rv = nsGenericHTMLElement::AfterSetAttr(aNameSpaceID,
-                                                   aName, aValue, aNotify);
+                                                   aName, aValue, aOldValue,
+                                                   aNotify);
   NS_ENSURE_SUCCESS(rv, rv);
   // if the last mapped attribute was removed, don't clear the
   // nsMappedAttributes, our style can still depend on the containing frame element
diff --git a/dom/html/HTMLBodyElement.h b/dom/html/HTMLBodyElement.h
index ad1f5d8721..6a888c71b7 100644
--- a/dom/html/HTMLBodyElement.h
+++ b/dom/html/HTMLBodyElement.h
@@ -117,7 +117,9 @@ public:
    * Called when an attribute has just been changed
    */
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
 protected:
   virtual ~HTMLBodyElement();
diff --git a/dom/html/HTMLButtonElement.cpp b/dom/html/HTMLButtonElement.cpp
index c26e60ed0f..1a76aac10a 100644
--- a/dom/html/HTMLButtonElement.cpp
+++ b/dom/html/HTMLButtonElement.cpp
@@ -437,7 +437,8 @@ HTMLButtonElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 HTMLButtonElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify)
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     if (aName == nsGkAtoms::type) {
@@ -452,7 +453,8 @@ HTMLButtonElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLFormElementWithState::AfterSetAttr(aNameSpaceID, aName,
-                                                         aValue, aNotify);
+                                                         aValue, aOldValue,
+                                                         aNotify);
 }
 
 NS_IMETHODIMP
diff --git a/dom/html/HTMLButtonElement.h b/dom/html/HTMLButtonElement.h
index 19c93e4839..8bab9fd48e 100644
--- a/dom/html/HTMLButtonElement.h
+++ b/dom/html/HTMLButtonElement.h
@@ -86,8 +86,10 @@ public:
   /**
    * Called when an attribute has just been changed
    */
-  nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
-                        const nsAttrValue* aValue, bool aNotify) override;
+  virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
   virtual bool ParseAttribute(int32_t aNamespaceID,
                               nsIAtom* aAttribute,
                               const nsAString& aValue,
diff --git a/dom/html/HTMLFieldSetElement.cpp b/dom/html/HTMLFieldSetElement.cpp
index c008b9b6d6..f546cad5b4 100644
--- a/dom/html/HTMLFieldSetElement.cpp
+++ b/dom/html/HTMLFieldSetElement.cpp
@@ -83,7 +83,8 @@ HTMLFieldSetElement::GetEventTargetParent(EventChainPreVisitor& aVisitor)
 
 nsresult
 HTMLFieldSetElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                  const nsAttrValue* aValue, bool aNotify)
+                                  const nsAttrValue* aValue,
+                                  const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::disabled &&
       nsINode::GetFirstChild()) {
@@ -100,7 +101,7 @@ HTMLFieldSetElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLFormElement::AfterSetAttr(aNameSpaceID, aName,
-                                                aValue, aNotify);
+                                                aValue, aOldValue, aNotify);
 }
 
 // nsIDOMHTMLFieldSetElement
diff --git a/dom/html/HTMLFieldSetElement.h b/dom/html/HTMLFieldSetElement.h
index 1e9f0214f5..2c0e9cc149 100644
--- a/dom/html/HTMLFieldSetElement.h
+++ b/dom/html/HTMLFieldSetElement.h
@@ -43,7 +43,9 @@ public:
   virtual nsresult GetEventTargetParent(
                      EventChainPreVisitor& aVisitor) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   virtual nsresult InsertChildAt(nsIContent* aChild, uint32_t aIndex,
                                      bool aNotify) override;
diff --git a/dom/html/HTMLFormElement.cpp b/dom/html/HTMLFormElement.cpp
index bdc05b053c..1fdfb602e1 100644
--- a/dom/html/HTMLFormElement.cpp
+++ b/dom/html/HTMLFormElement.cpp
@@ -214,7 +214,8 @@ HTMLFormElement::SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 HTMLFormElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                              const nsAttrValue* aValue, bool aNotify)
+                              const nsAttrValue* aValue,
+                              const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aName == nsGkAtoms::novalidate && aNameSpaceID == kNameSpaceID_None) {
     // Update all form elements states because they might be [no longer]
@@ -230,7 +231,8 @@ HTMLFormElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
     }
   }
 
-  return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue, aNotify);
+  return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
+                                            aOldValue, aNotify);
 }
 
 NS_IMPL_STRING_ATTR(HTMLFormElement, AcceptCharset, acceptcharset)
diff --git a/dom/html/HTMLFormElement.h b/dom/html/HTMLFormElement.h
index e45d4c10d7..6102ea61f1 100644
--- a/dom/html/HTMLFormElement.h
+++ b/dom/html/HTMLFormElement.h
@@ -114,7 +114,9 @@ public:
                            nsIAtom* aPrefix, const nsAString& aValue,
                            bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   /**
    * Forget all information about the current submission (and the fact that we
diff --git a/dom/html/HTMLIFrameElement.cpp b/dom/html/HTMLIFrameElement.cpp
index 0d5a209c04..6ae4ec9ddd 100644
--- a/dom/html/HTMLIFrameElement.cpp
+++ b/dom/html/HTMLIFrameElement.cpp
@@ -202,7 +202,7 @@ HTMLIFrameElement::SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 nsresult
 HTMLIFrameElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
-                                bool aNotify)
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aName == nsGkAtoms::sandbox &&
       aNameSpaceID == kNameSpaceID_None && mFrameLoader) {
@@ -212,7 +212,7 @@ HTMLIFrameElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
     mFrameLoader->ApplySandboxFlags(GetSandboxFlags());
   }
   return nsGenericHTMLFrameElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                                 aNotify);
+                                                 aOldValue, aNotify);
 }
 
 nsresult
diff --git a/dom/html/HTMLIFrameElement.h b/dom/html/HTMLIFrameElement.h
index 5bfda24700..23afaaddd0 100644
--- a/dom/html/HTMLIFrameElement.h
+++ b/dom/html/HTMLIFrameElement.h
@@ -56,6 +56,7 @@ public:
                            bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
                                 bool aNotify) override;
   virtual nsresult UnsetAttr(int32_t aNameSpaceID, nsIAtom* aAttribute,
                              bool aNotify) override;
diff --git a/dom/html/HTMLImageElement.cpp b/dom/html/HTMLImageElement.cpp
index 5d0cfd15eb..dd43ac36ad 100644
--- a/dom/html/HTMLImageElement.cpp
+++ b/dom/html/HTMLImageElement.cpp
@@ -391,7 +391,8 @@ HTMLImageElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 HTMLImageElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                               const nsAttrValue* aValue, bool aNotify)
+                               const nsAttrValue* aValue,
+                               const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None && mForm &&
       (aName == nsGkAtoms::name || aName == nsGkAtoms::id) &&
@@ -433,7 +434,7 @@ HTMLImageElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName,
-                                            aValue, aNotify);
+                                            aValue, aOldValue, aNotify);
 }
 
 nsresult
diff --git a/dom/html/HTMLImageElement.h b/dom/html/HTMLImageElement.h
index d92cd84b81..52480d0a05 100644
--- a/dom/html/HTMLImageElement.h
+++ b/dom/html/HTMLImageElement.h
@@ -348,7 +348,9 @@ protected:
                                  bool aNotify) override;
 
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   // This is a weak reference that this element and the HTMLFormElement
   // cooperate in maintaining.
diff --git a/dom/html/HTMLInputElement.cpp b/dom/html/HTMLInputElement.cpp
index 1d3db145ac..7c2688b7ed 100644
--- a/dom/html/HTMLInputElement.cpp
+++ b/dom/html/HTMLInputElement.cpp
@@ -1287,7 +1287,8 @@ HTMLInputElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 HTMLInputElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                               const nsAttrValue* aValue, bool aNotify)
+                               const nsAttrValue* aValue,
+                               const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     //
@@ -1437,7 +1438,8 @@ HTMLInputElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLFormElementWithState::AfterSetAttr(aNameSpaceID, aName,
-                                                         aValue, aNotify);
+                                                         aValue, aOldValue,
+                                                         aNotify);
 }
 
 // nsIDOMHTMLInputElement
diff --git a/dom/html/HTMLInputElement.h b/dom/html/HTMLInputElement.h
index d6a078f0bf..48807f7337 100644
--- a/dom/html/HTMLInputElement.h
+++ b/dom/html/HTMLInputElement.h
@@ -964,7 +964,9 @@ protected:
    * Called when an attribute has just been changed
    */
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   /**
    * Dispatch a select event. Returns true if the event was not cancelled.
diff --git a/dom/html/HTMLLinkElement.cpp b/dom/html/HTMLLinkElement.cpp
index 4c42d310a6..b05b92d7aa 100644
--- a/dom/html/HTMLLinkElement.cpp
+++ b/dom/html/HTMLLinkElement.cpp
@@ -348,7 +348,8 @@ HTMLLinkElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 HTMLLinkElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                              const nsAttrValue* aValue, bool aNotify)
+                              const nsAttrValue* aValue,
+                              const nsAttrValue* aOldValue, bool aNotify)
 {
   // It's safe to call ResetLinkState here because our new attr value has
   // already been set or unset.  ResetLinkState needs the updated attribute
@@ -417,7 +418,7 @@ HTMLLinkElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 nsresult
diff --git a/dom/html/HTMLLinkElement.h b/dom/html/HTMLLinkElement.h
index 9c69cfb13c..acac955cb2 100644
--- a/dom/html/HTMLLinkElement.h
+++ b/dom/html/HTMLLinkElement.h
@@ -66,6 +66,7 @@ public:
                                  bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
                                 bool aNotify) override;
   virtual bool IsLink(nsIURI** aURI) const override;
   virtual already_AddRefed<nsIURI> GetHrefURI() const override;
diff --git a/dom/html/HTMLMediaElement.cpp b/dom/html/HTMLMediaElement.cpp
index bc63eab512..4bcc188d39 100644
--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -3774,7 +3774,8 @@ nsresult HTMLMediaElement::UnsetAttr(int32_t aNameSpaceID, nsIAtom* aAttr,
 
 nsresult
 HTMLMediaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify)
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::src) {
     mSrcMediaSource = nullptr;
@@ -3796,7 +3797,7 @@ HTMLMediaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName,
-                                            aValue, aNotify);
+                                            aValue, aOldValue, aNotify);
 }
 
 nsresult HTMLMediaElement::BindToTree(nsIDocument* aDocument, nsIContent* aParent,
diff --git a/dom/html/HTMLMediaElement.h b/dom/html/HTMLMediaElement.h
index 44c666f951..d81e9f5918 100644
--- a/dom/html/HTMLMediaElement.h
+++ b/dom/html/HTMLMediaElement.h
@@ -146,6 +146,7 @@ public:
                              bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
                                 bool aNotify) override;
 
   virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
diff --git a/dom/html/HTMLMenuItemElement.cpp b/dom/html/HTMLMenuItemElement.cpp
index 6a8ad8174c..3245a16b1d 100644
--- a/dom/html/HTMLMenuItemElement.cpp
+++ b/dom/html/HTMLMenuItemElement.cpp
@@ -380,7 +380,8 @@ HTMLMenuItemElement::GetText(nsAString& aText)
 
 nsresult
 HTMLMenuItemElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                  const nsAttrValue* aValue, bool aNotify)
+                                  const nsAttrValue* aValue,
+                                  const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     if ((aName == nsGkAtoms::radiogroup || aName == nsGkAtoms::type) &&
@@ -404,7 +405,7 @@ HTMLMenuItemElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 void
diff --git a/dom/html/HTMLMenuItemElement.h b/dom/html/HTMLMenuItemElement.h
index 1da63edd05..cb824edcc5 100644
--- a/dom/html/HTMLMenuItemElement.h
+++ b/dom/html/HTMLMenuItemElement.h
@@ -125,7 +125,9 @@ protected:
 
 protected:
   virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   void WalkRadioGroup(Visitor* aVisitor);
 
diff --git a/dom/html/HTMLMetaElement.cpp b/dom/html/HTMLMetaElement.cpp
index 47effa2bc5..833c3177a7 100644
--- a/dom/html/HTMLMetaElement.cpp
+++ b/dom/html/HTMLMetaElement.cpp
@@ -60,7 +60,8 @@ HTMLMetaElement::SetMetaReferrer(nsIDocument* aDocument)
 
 nsresult
 HTMLMetaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                              const nsAttrValue* aValue, bool aNotify)
+                              const nsAttrValue* aValue,
+                              const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     nsIDocument *document = GetUncomposedDoc();
@@ -82,7 +83,7 @@ HTMLMetaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 nsresult
diff --git a/dom/html/HTMLMetaElement.h b/dom/html/HTMLMetaElement.h
index d3f05826d4..0b9117e557 100644
--- a/dom/html/HTMLMetaElement.h
+++ b/dom/html/HTMLMetaElement.h
@@ -33,7 +33,9 @@ public:
                               bool aNullParent = true) override;
 
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   void CreateAndDispatchEvent(nsIDocument* aDoc, const nsAString& aEventName);
 
diff --git a/dom/html/HTMLOptGroupElement.cpp b/dom/html/HTMLOptGroupElement.cpp
index 0424ccef32..63af4e39f3 100644
--- a/dom/html/HTMLOptGroupElement.cpp
+++ b/dom/html/HTMLOptGroupElement.cpp
@@ -101,7 +101,8 @@ HTMLOptGroupElement::RemoveChildAt(uint32_t aIndex, bool aNotify)
 
 nsresult
 HTMLOptGroupElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                  const nsAttrValue* aValue, bool aNotify)
+                                  const nsAttrValue* aValue,
+                                  const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::disabled) {
     // All our children <option> have their :disabled state depending on our
@@ -116,7 +117,7 @@ HTMLOptGroupElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 EventStates
diff --git a/dom/html/HTMLOptGroupElement.h b/dom/html/HTMLOptGroupElement.h
index c669f43b48..6853e51ed7 100644
--- a/dom/html/HTMLOptGroupElement.h
+++ b/dom/html/HTMLOptGroupElement.h
@@ -43,7 +43,9 @@ public:
   virtual nsresult Clone(mozilla::dom::NodeInfo* aNodeInfo, nsINode** aResult) const override;
 
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   virtual nsIDOMNode* AsDOMNode() override { return this; }
 
diff --git a/dom/html/HTMLOptionElement.cpp b/dom/html/HTMLOptionElement.cpp
index 9d861d4145..410c5713ea 100644
--- a/dom/html/HTMLOptionElement.cpp
+++ b/dom/html/HTMLOptionElement.cpp
@@ -244,7 +244,8 @@ HTMLOptionElement::BeforeSetAttr(int32_t aNamespaceID, nsIAtom* aName,
 
 nsresult
 HTMLOptionElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify)
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None &&
       aName == nsGkAtoms::value && Selected()) {
@@ -258,7 +259,7 @@ HTMLOptionElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName,
-                                            aValue, aNotify);
+                                            aValue, aOldValue, aNotify);
 }
 
 NS_IMETHODIMP
diff --git a/dom/html/HTMLOptionElement.h b/dom/html/HTMLOptionElement.h
index 23ef2fb5e6..965cdeb8f2 100644
--- a/dom/html/HTMLOptionElement.h
+++ b/dom/html/HTMLOptionElement.h
@@ -50,7 +50,9 @@ public:
                                  const nsAttrValueOrString* aValue,
                                  bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   void SetSelectedInternal(bool aValue, bool aNotify);
 
diff --git a/dom/html/HTMLScriptElement.cpp b/dom/html/HTMLScriptElement.cpp
index 095b9b77de..a1bea94d97 100644
--- a/dom/html/HTMLScriptElement.cpp
+++ b/dom/html/HTMLScriptElement.cpp
@@ -232,13 +232,14 @@ HTMLScriptElement::SetNoModule(bool aValue, ErrorResult& aRv)
 
 nsresult
 HTMLScriptElement::AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify)
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   if (nsGkAtoms::async == aName && kNameSpaceID_None == aNamespaceID) {
     mForceAsync = false;
   }
   return nsGenericHTMLElement::AfterSetAttr(aNamespaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 NS_IMETHODIMP
diff --git a/dom/html/HTMLScriptElement.h b/dom/html/HTMLScriptElement.h
index 19ceb414f9..bd446fa97d 100644
--- a/dom/html/HTMLScriptElement.h
+++ b/dom/html/HTMLScriptElement.h
@@ -57,7 +57,9 @@ public:
 
   // Element
   virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   // WebIDL
   void SetText(const nsAString& aValue, ErrorResult& rv);
diff --git a/dom/html/HTMLSelectElement.cpp b/dom/html/HTMLSelectElement.cpp
index a5f88f3fb5..d11f8b90f0 100644
--- a/dom/html/HTMLSelectElement.cpp
+++ b/dom/html/HTMLSelectElement.cpp
@@ -1283,7 +1283,8 @@ HTMLSelectElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 HTMLSelectElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify)
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     if (aName == nsGkAtoms::disabled) {
@@ -1297,7 +1298,8 @@ HTMLSelectElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLFormElementWithState::AfterSetAttr(aNameSpaceID, aName,
-                                                         aValue, aNotify);
+                                                         aValue, aOldValue,
+                                                         aNotify);
 }
 
 nsresult
diff --git a/dom/html/HTMLSelectElement.h b/dom/html/HTMLSelectElement.h
index 8eb7fa410d..90e13da7a2 100644
--- a/dom/html/HTMLSelectElement.h
+++ b/dom/html/HTMLSelectElement.h
@@ -378,7 +378,9 @@ public:
                                  const nsAttrValueOrString* aValue,
                                  bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
   virtual nsresult UnsetAttr(int32_t aNameSpaceID, nsIAtom* aAttribute,
                              bool aNotify) override;
 
diff --git a/dom/html/HTMLSourceElement.cpp b/dom/html/HTMLSourceElement.cpp
index 73d9c9d8cb..93a17ea8c1 100644
--- a/dom/html/HTMLSourceElement.cpp
+++ b/dom/html/HTMLSourceElement.cpp
@@ -98,7 +98,8 @@ HTMLSourceElement::UpdateMediaList(const nsAttrValue* aValue)
 
 nsresult
 HTMLSourceElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify)
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue, bool aNotify)
 {
   // If we are associated with a <picture> with a valid <img>, notify it of
   // responsive parameter changes
@@ -143,7 +144,7 @@ HTMLSourceElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName,
-                                            aValue, aNotify);
+                                            aValue, aOldValue, aNotify);
 }
 
 nsresult
diff --git a/dom/html/HTMLSourceElement.h b/dom/html/HTMLSourceElement.h
index 595e21015b..71b676c2c5 100644
--- a/dom/html/HTMLSourceElement.h
+++ b/dom/html/HTMLSourceElement.h
@@ -110,6 +110,7 @@ protected:
 protected:
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
                                 bool aNotify) override;
 
 private:
diff --git a/dom/html/HTMLStyleElement.cpp b/dom/html/HTMLStyleElement.cpp
index 329dda6480..743f4addb9 100644
--- a/dom/html/HTMLStyleElement.cpp
+++ b/dom/html/HTMLStyleElement.cpp
@@ -171,7 +171,8 @@ HTMLStyleElement::UnbindFromTree(bool aDeep, bool aNullParent)
 
 nsresult
 HTMLStyleElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                               const nsAttrValue* aValue, bool aNotify)
+                               const nsAttrValue* aValue,
+                               const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     if (aName == nsGkAtoms::title ||
@@ -185,7 +186,7 @@ HTMLStyleElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 NS_IMETHODIMP
diff --git a/dom/html/HTMLStyleElement.h b/dom/html/HTMLStyleElement.h
index 6b2a12b1fe..bd69a6aa1a 100644
--- a/dom/html/HTMLStyleElement.h
+++ b/dom/html/HTMLStyleElement.h
@@ -48,6 +48,7 @@ public:
                               bool aNullParent = true) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
                                 bool aNotify) override;
 
   virtual nsresult Clone(mozilla::dom::NodeInfo *aNodeInfo, nsINode **aResult) const override;
diff --git a/dom/html/HTMLTableElement.cpp b/dom/html/HTMLTableElement.cpp
index df84a0f77d..e6aa71e51e 100644
--- a/dom/html/HTMLTableElement.cpp
+++ b/dom/html/HTMLTableElement.cpp
@@ -933,7 +933,9 @@ HTMLTableElement::BuildInheritedAttributes()
 
       if (modifiableMapped) {
         nsAttrValue val(*value);
-        modifiableMapped->SetAndTakeAttr(nsGkAtoms::cellpadding, val);
+        bool oldValueSet;
+        modifiableMapped->SetAndSwapAttr(nsGkAtoms::cellpadding, val,
+                                         &oldValueSet);
       }
       newAttrs = sheet->UniqueMappedAttributes(modifiableMapped);
       NS_ASSERTION(newAttrs, "out of memory, but handling gracefully");
@@ -994,13 +996,13 @@ HTMLTableElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 nsresult
 HTMLTableElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                const nsAttrValue* aValue,
-                               bool aNotify)
+                               const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aName == nsGkAtoms::cellpadding && aNameSpaceID == kNameSpaceID_None) {
     BuildInheritedAttributes();
   }
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 } // namespace dom
diff --git a/dom/html/HTMLTableElement.h b/dom/html/HTMLTableElement.h
index 0e907cf54f..ce9d224b93 100644
--- a/dom/html/HTMLTableElement.h
+++ b/dom/html/HTMLTableElement.h
@@ -194,7 +194,9 @@ public:
    * Called when an attribute has just been changed
    */
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(HTMLTableElement,
                                            nsGenericHTMLElement)
diff --git a/dom/html/HTMLTextAreaElement.cpp b/dom/html/HTMLTextAreaElement.cpp
index c929daebd9..f25241d60e 100644
--- a/dom/html/HTMLTextAreaElement.cpp
+++ b/dom/html/HTMLTextAreaElement.cpp
@@ -1348,7 +1348,8 @@ HTMLTextAreaElement::ContentChanged(nsIContent* aContent)
 
 nsresult
 HTMLTextAreaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                  const nsAttrValue* aValue, bool aNotify)
+                                  const nsAttrValue* aValue,
+                                  const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     if (aName == nsGkAtoms::required || aName == nsGkAtoms::disabled ||
@@ -1367,7 +1368,7 @@ HTMLTextAreaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLFormElementWithState::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                                         aNotify);
+                                                         aOldValue, aNotify);
   }
 
 nsresult
diff --git a/dom/html/HTMLTextAreaElement.h b/dom/html/HTMLTextAreaElement.h
index 8723e85f68..5ab58554ec 100644
--- a/dom/html/HTMLTextAreaElement.h
+++ b/dom/html/HTMLTextAreaElement.h
@@ -357,7 +357,9 @@ protected:
   void ContentChanged(nsIContent* aContent);
 
   virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom *aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   /**
    * Return if an element should have a specific validity UI
diff --git a/dom/html/nsGenericHTMLElement.cpp b/dom/html/nsGenericHTMLElement.cpp
index 30ecd8508d..569dae6c26 100644
--- a/dom/html/nsGenericHTMLElement.cpp
+++ b/dom/html/nsGenericHTMLElement.cpp
@@ -656,7 +656,8 @@ nsGenericHTMLElement::GetHrefURIForAnchors() const
 
 nsresult
 nsGenericHTMLElement::AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
-                                   const nsAttrValue* aValue, bool aNotify)
+                                   const nsAttrValue* aValue,
+                                   const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNamespaceID == kNameSpaceID_None) {
     if (IsEventAttributeName(aName) && aValue) {
@@ -697,7 +698,7 @@ nsGenericHTMLElement::AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElementBase::AfterSetAttr(aNamespaceID, aName,
-                                                aValue, aNotify);
+                                                aValue, aOldValue, aNotify);
 }
 
 EventListenerManager*
@@ -2015,7 +2016,8 @@ nsGenericHTMLFormElement::BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
 
 nsresult
 nsGenericHTMLFormElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                       const nsAttrValue* aValue, bool aNotify)
+                                       const nsAttrValue* aValue,
+                                       const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aNameSpaceID == kNameSpaceID_None) {
     // add the control to the hashtable as needed
@@ -2064,7 +2066,7 @@ nsGenericHTMLFormElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName,
-                                            aValue, aNotify);
+                                            aValue, aOldValue, aNotify);
 }
 
 nsresult
diff --git a/dom/html/nsGenericHTMLElement.h b/dom/html/nsGenericHTMLElement.h
index a8a0d2596c..b9c0340493 100644
--- a/dom/html/nsGenericHTMLElement.h
+++ b/dom/html/nsGenericHTMLElement.h
@@ -915,7 +915,9 @@ private:
 
 protected:
   virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   virtual mozilla::EventListenerManager*
     GetEventListenerManagerForAttr(nsIAtom* aAttrName,
@@ -1267,7 +1269,9 @@ protected:
                                  bool aNotify) override;
 
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
-                                const nsAttrValue* aValue, bool aNotify) override;
+                                const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
+                                bool aNotify) override;
 
   /**
    * This method will update the form owner, using @form or looking to a parent.
diff --git a/dom/html/nsGenericHTMLFrameElement.cpp b/dom/html/nsGenericHTMLFrameElement.cpp
index 0a69116a18..1aeb0a7d2e 100644
--- a/dom/html/nsGenericHTMLFrameElement.cpp
+++ b/dom/html/nsGenericHTMLFrameElement.cpp
@@ -413,7 +413,7 @@ PrincipalAllowsBrowserFrame(nsIPrincipal* aPrincipal)
 /* virtual */ nsresult
 nsGenericHTMLFrameElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                         const nsAttrValue* aValue,
-                                        bool aNotify)
+                                        const nsAttrValue* aOldValue, bool aNotify)
 {
   if (aName == nsGkAtoms::scrolling && aNameSpaceID == kNameSpaceID_None) {
     if (mFrameLoader) {
@@ -445,7 +445,7 @@ nsGenericHTMLFrameElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
   }
 
   return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
-                                            aNotify);
+                                            aOldValue, aNotify);
 }
 
 void
diff --git a/dom/html/nsGenericHTMLFrameElement.h b/dom/html/nsGenericHTMLFrameElement.h
index 0367a7fe11..1570b19563 100644
--- a/dom/html/nsGenericHTMLFrameElement.h
+++ b/dom/html/nsGenericHTMLFrameElement.h
@@ -65,6 +65,7 @@ public:
                              bool aNotify) override;
   virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 const nsAttrValue* aValue,
+                                const nsAttrValue* aOldValue,
                                 bool aNotify) override;
   virtual void DestroyContent() override;