Issue #2176 - Don't reconstruct the parent when tearing down

display:contents nodes with pseudo-elements.

We need to use StyleChildrenIterator which iterates over them, instead.
This is a bit of a hack but we can't always have our cake.

We need to be a bit careful though, since ::before and ::after are owned
by their own frame, and thus could be unbound from the tree or even dead
after removing the frame.

This basically ports bugs 1435566 and 1438467

1 files changed, 16 insertions, 30 deletions

diff --git a/layout/base/nsCSSFrameConstructor.cpp b/layout/base/nsCSSFrameConstructor.cpp
index 8293e5198c..6a512891f9 100644
--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@@ -8137,26 +8137,10 @@ nsCSSFrameConstructor::ContentRemoved(nsIContent* aContainer,
   MOZ_ASSERT(!childFrame || !GetDisplayContentsStyleFor(aChild),
              "display:contents nodes shouldn't have a frame");
   if (!childFrame && GetDisplayContentsStyleFor(aChild)) {
-    nsIContent* ancestor = aChild->GetFlattenedTreeParent();
-    MOZ_ASSERT(ancestor, "display: contents on the root?");
-    while (!ancestor->GetPrimaryFrame()) {
-      ancestor = ancestor->GetFlattenedTreeParent();
-      MOZ_ASSERT(ancestor, "we can't have a display: contents subtree root!");
-    }
-
-    nsIFrame* ancestorFrame = ancestor->GetPrimaryFrame();
-    if (ancestorFrame->GetProperty(nsIFrame::GenConProperty())) {
-      *aDidReconstruct = true;
-
-      // XXXmats Can we recreate frames only for the ::after/::before content?
-      // XXX Perhaps even only those that belong to the aChild sub-tree?
-      LAYOUT_PHASE_TEMP_EXIT();
-      RecreateFramesForContent(ancestor, insertionKind, aFlags);
-      LAYOUT_PHASE_TEMP_REENTER();
-      return;
-    }
-
-    FlattenedChildIterator iter(aChild);
+    // NOTE(emilio): We may iterate through ::before and ::after here and they
+    // may be gone after the respective ContentRemoved call. Right now
+    // StyleChildrenIterator handles that properly, so it's not an issue.
+    StyleChildrenIterator iter(aChild);
     for (nsIContent* c = iter.GetNextChild(); c; c = iter.GetNextChild()) {
       if (c->GetPrimaryFrame() || GetDisplayContentsStyleFor(c)) {
         LAYOUT_PHASE_TEMP_EXIT();
@@ -8333,8 +8317,13 @@ nsCSSFrameConstructor::ContentRemoved(nsIContent* aContainer,
       NS_ASSERTION(childFrame, "Missing placeholder frame for out of flow.");
       parentFrame = childFrame->GetParent();
     }
+
     RemoveFrame(nsLayoutUtils::GetChildListNameFor(childFrame), childFrame);
 
+    // NOTE(emilio): aChild could be dead here already if it is a ::before or

+    // ::after pseudo-element (since in that case it was owned by childFrame,

+    // which we just destroyed).

+
     if (isRoot) {
       mRootElementFrame = nullptr;
       mRootElementStyleFrame = nullptr;
@@ -8354,8 +8343,7 @@ nsCSSFrameConstructor::ContentRemoved(nsIContent* aContainer,
     // to do this if the table parent type of our parent type is not
     // eTypeBlock, though, because in that case the whitespace isn't
     // being suppressed due to us anyway.
-    if (aContainer && !aChild->IsRootOfAnonymousSubtree() &&
-        aFlags == REMOVE_CONTENT &&
+    if (aContainer && aOldNextSibling && aFlags == REMOVE_CONTENT &&
         GetParentType(parentType) == eTypeBlock) {
       // Adjacent whitespace-only text nodes might have been suppressed if
       // this node does not have inline ends. Create frames for them now
@@ -8370,17 +8358,15 @@ nsCSSFrameConstructor::ContentRemoved(nsIContent* aContainer,
       //
       // FIXME(emilio): This should probably use the lazy frame construction
       // bits if possible instead of reframing it in place.
-      if (aOldNextSibling) {
-        nsIContent* prevSibling = aOldNextSibling->GetPreviousSibling();
-        if (prevSibling && prevSibling->GetPreviousSibling()) {
-          LAYOUT_PHASE_TEMP_EXIT();
-          ReframeTextIfNeeded(aContainer, prevSibling);
-          LAYOUT_PHASE_TEMP_REENTER();
-        }
+      nsIContent* prevSibling = aOldNextSibling->GetPreviousSibling();
+      if (prevSibling && prevSibling->GetPreviousSibling()) {
+        LAYOUT_PHASE_TEMP_EXIT();
+        ReframeTextIfNeeded(aContainer, prevSibling);
+        LAYOUT_PHASE_TEMP_REENTER();
       }
       // Reframe any text node just after the node being removed, if there is
       // one, and if it's not the last child or the first child.
-      if (aOldNextSibling && aOldNextSibling->GetNextSibling() &&
+      if (aOldNextSibling->GetNextSibling() &&
           aOldNextSibling->GetPreviousSibling()) {
         LAYOUT_PHASE_TEMP_EXIT();
         ReframeTextIfNeeded(aContainer, aOldNextSibling);