Don't early out recursion into PaintLayerChildren when computing composited bounds.

third_party/WebKit/Source/core/paint/PaintLayer.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights
  * reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
@@ skipping 2520 matching lines @@
   if (isRootLayer() && !needsCompositedScrolling())
     return LayoutRect(m_layoutObject->view()->documentRect());
 
   // The layer created for the LayoutFlowThread is just a helper for painting
   // and hit-testing, and should not contribute to the bounding box. The
   // LayoutMultiColumnSets will contribute the correct size for the layout
   // content of the multicol container.
   if (layoutObject()->isLayoutFlowThread())
     return LayoutRect();
 
+  const_cast<PaintLayer*>(this)->stackingNode()->updateLayerListsIfNeeded();
+
   // If there is a clip applied by an ancestor to this PaintLayer but below or
   // equal to |ancestorLayer|, use that clip as the bounds rather than the
   // recursive bounding boxes, since the latter may be larger than the actual
   // size. See https://bugs.webkit.org/show_bug.cgi?id=80372 for examples.
   LayoutRect result = clipper().localClipRect(ancestorLayer);
   // TODO(chrishtr): avoid converting to IntRect and back.
-  if (result == LayoutRect(LayoutRect::infiniteIntRect())) {
+  if (result == LayoutRect(LayoutRect::infiniteIntRect()))
     result = physicalBoundingBox(LayoutPoint());
 
-    const_cast<PaintLayer*>(this)->stackingNode()->updateLayerListsIfNeeded();
+  expandRectForStackingChildren(this, result, options);
 
-    expandRectForStackingChildren(this, result, options);
-
-    // Only enlarge by the filter outsets if we know the filter is going to be
-    // rendered in software.  Accelerated filters will handle their own outsets.
-    if (paintsWithFilters())
-      result = mapLayoutRectForFilter(result);
-  }
+  // Only enlarge by the filter outsets if we know the filter is going to be
+  // rendered in software.  Accelerated filters will handle their own outsets.
+  if (paintsWithFilters())
+    result = mapLayoutRectForFilter(result);
 
   if (transform() && (options == IncludeTransformsAndCompositedChildLayers ||
                       ((paintsWithTransform(GlobalPaintNormalPhase) &&
                         (this != ancestorLayer ||
                          options == MaybeIncludeTransformForAncestorLayer)))))
     result = transform()->mapRect(result);
 
   if (shouldFragmentCompositedBounds(ancestorLayer)) {
     convertFromFlowThreadToVisualBoundingBoxInAncestor(ancestorLayer, result);
     return result;
@@ skipping 660 matching lines @@
 }
 
 void showLayerTree(const blink::LayoutObject* layoutObject) {
   if (!layoutObject) {
     fprintf(stderr, "Cannot showLayerTree. Root is (nil)\n");
     return;
   }
   showLayerTree(layoutObject->enclosingLayer());
 }
 #endif