Bug 1153695 - Wrap nsAutoOOFFrameList in a scope to ensure its dtor runs before the VerifyOverflowSituation() call (to avoid frames appearing to be on two child lists). r=roc

layout/generic/nsBlockFrame.cpp

@@ -4713,18 +4713,20 @@ nsBlockFrame::DrainSelfOverflowList()
 
   // No need to reparent frames in our own overflow lines/oofs, because they're
   // already ours. But we should put overflow floats back in mFloats.
-  nsAutoOOFFrameList oofs(this);
-  if (oofs.mList.NotEmpty()) {
+  // (explicit scope to remove the OOF list before VerifyOverflowSituation)
+  {
+    nsAutoOOFFrameList oofs(this);
+    if (oofs.mList.NotEmpty()) {
 #ifdef DEBUG
-    for (nsIFrame* f : oofs.mList) {
-      MOZ_ASSERT(!(f->GetStateBits() & NS_FRAME_IS_PUSHED_FLOAT),
-                 "CollectFloats should've removed that bit");
-    }
+      for (nsIFrame* f : oofs.mList) {
+        MOZ_ASSERT(!(f->GetStateBits() & NS_FRAME_IS_PUSHED_FLOAT),
+                   "CollectFloats should've removed that bit");
+      }
 #endif
-    // The overflow floats go after our regular floats.
-    mFloats.AppendFrames(nullptr, oofs.mList);
+      // The overflow floats go after our regular floats.
+      mFloats.AppendFrames(nullptr, oofs.mList);
+    }
   }
-
   if (!ourOverflowLines->mLines.empty()) {
     mFrames.AppendFrames(nullptr, ourOverflowLines->mFrames);
     mLines.splice(mLines.end(), ourOverflowLines->mLines);