Bug 1032613 part 1: Promote FrameMaintainsOverflow to be a public nsIFrame method, & implement it using HasAllStateBits. r=dbaron

layout/base/RestyleManager.cpp

@@ -818,8 +818,7 @@ RestyleManager::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
     } else {
       NS_ASSERTION(frame, "This shouldn't happen");
 
-      if ((frame->GetStateBits() & NS_FRAME_SVG_LAYOUT) &&
-          (frame->GetStateBits() & NS_FRAME_IS_NONDISPLAY)) {
+      if (!frame->FrameMaintainsOverflow()) {
         // frame does not maintain overflow rects, so avoid calling
         // FinishAndStoreOverflow on it:
         hint = NS_SubtractHint(hint,

layout/generic/nsFrame.cpp

@@ -5555,18 +5555,10 @@ nsIFrame::GetPreEffectsVisualOverflowRect() const
   return r ? *r : GetVisualOverflowRectRelativeToSelf();
 }
 
-inline static bool
-FrameMaintainsOverflow(nsIFrame* aFrame)
-{
-  return (aFrame->GetStateBits() &
-          (NS_FRAME_SVG_LAYOUT | NS_FRAME_IS_NONDISPLAY)) !=
-         (NS_FRAME_SVG_LAYOUT | NS_FRAME_IS_NONDISPLAY);
-}
-
 /* virtual */ bool
 nsFrame::UpdateOverflow()
 {
-  MOZ_ASSERT(FrameMaintainsOverflow(this),
+  MOZ_ASSERT(FrameMaintainsOverflow(),
              "Non-display SVG do not maintain visual overflow rects");
 
   nsRect rect(nsPoint(0, 0), GetSize());
@@ -7586,7 +7578,7 @@ bool
 nsIFrame::FinishAndStoreOverflow(nsOverflowAreas& aOverflowAreas,
                                  nsSize aNewSize, nsSize* aOldSize)
 {
-  NS_ASSERTION(FrameMaintainsOverflow(this),
+  NS_ASSERTION(FrameMaintainsOverflow(),
                "Don't call - overflow rects not maintained on these SVG frames");
 
   nsRect bounds(nsPoint(0, 0), aNewSize);
@@ -7744,7 +7736,7 @@ nsIFrame::RecomputePerspectiveChildrenOverflow(const nsIFrame* aStartFrame, cons
     nsFrameList::Enumerator childFrames(lists.CurrentList());
     for (; !childFrames.AtEnd(); childFrames.Next()) {
       nsIFrame* child = childFrames.get();
-      if (!FrameMaintainsOverflow(child)) {
+      if (!child->FrameMaintainsOverflow()) {
         continue; // frame does not maintain overflow rects
       }
       if (child->HasPerspective()) {
@@ -7792,7 +7784,7 @@ RecomputePreserve3DChildrenOverflow(nsIFrame* aFrame, const nsRect* aBounds)
     nsFrameList::Enumerator childFrames(lists.CurrentList());
     for (; !childFrames.AtEnd(); childFrames.Next()) {
       nsIFrame* child = childFrames.get();
-      if (!FrameMaintainsOverflow(child)) {
+      if (!child->FrameMaintainsOverflow()) {
         continue; // frame does not maintain overflow rects
       }
       if (child->Extend3DContext()) {

layout/generic/nsIFrame.h

@@ -3027,6 +3027,15 @@ NS_PTR_TO_INT32(frame->Properties().Get(nsIFrame::ParagraphDepthProperty()))
     return GetStateBits() & NS_FRAME_FONT_INFLATION_CONTAINER;
   }
 
+  /**
+   * Return whether this frame keeps track of overflow areas. (Frames for
+   * non-display SVG elements -- e.g. <clipPath> -- do not maintain overflow
+   * areas, because they're never painted.)
+   */
+  bool FrameMaintainsOverflow() const {
+    return !HasAllStateBits(NS_FRAME_SVG_LAYOUT | NS_FRAME_IS_NONDISPLAY);
+  }
+
   /**
    * Returns the content node within the anonymous content that this frame
    * generated and which corresponds to the specified pseudo-element type,