Issue #2135 - Destroy the host frame and restyle when there are content changes

This is likely inefficient, but I haven't found a way other than this to ensure that the host frame is updated if the inserted/removed content isn't slotted. I'm assuming that Firefox is handling this somewhere else (and may have been even moved to Stylo), but was mentioned in an m-c bug we haven't seen yet. In fact, this is actually similar to how we handled elements passed to ContentInserted before landing e31ed5b07466d4a579fe4b025f97c971003fbc3f.

1 files changed, 14 insertions, 0 deletions

diff --git a/dom/base/ShadowRoot.cpp b/dom/base/ShadowRoot.cpp
index e31b97262c..92d5a2f2a9 100644
--- a/dom/base/ShadowRoot.cpp
+++ b/dom/base/ShadowRoot.cpp
@@ -578,6 +578,13 @@ ShadowRoot::ContentInserted(nsIDocument* aDocument,
   if (slot && slot->GetContainingShadow() == this &&
       slot->AssignedNodes().IsEmpty()) {
     slot->EnqueueSlotChangeEvent();
+    return;
+  }
+  
+  // XXX: The following makes the host destroy its frames and force a
+  // restyle for cases where the content isn't slotted.
+  if (aContainer == this) {
+    DistributionChanged();
   }
 }
 
@@ -614,6 +621,13 @@ ShadowRoot::ContentRemoved(nsIDocument* aDocument,
   if (slot && slot->GetContainingShadow() == this &&
       slot->AssignedNodes().IsEmpty()) {
     slot->EnqueueSlotChangeEvent();
+    return;
+  }
+
+  // XXX: The following makes the host destroy its frames and force a
+  // restyle for cases where the content isn't slotted.
+  if (aContainer == this) {
+    DistributionChanged();
   }
 }