Allow paint invalidation containers to cross frame boundaries.

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index 94adce2fe09a9165785e2c19c7d3206a991f3672..0de351cd052681cfa9f7e5f0aa5095e6e3e32a82 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -1422,13 +1422,11 @@ const RenderLayerModelObject* RenderObject::containerForPaintInvalidation() cons
 const RenderLayerModelObject* RenderObject::enclosingCompositedContainer() const
 {
     RenderLayerModelObject* container = 0;
-    if (view()->usesCompositing()) {
-        // FIXME: CompositingState is not necessarily up to date for many callers of this function.
-        DisableCompositingQueryAsserts disabler;
+    // FIXME: CompositingState is not necessarily up to date for many callers of this function.
+    DisableCompositingQueryAsserts disabler;
 
-        if (RenderLayer* compositingLayer = enclosingLayer()->enclosingLayerForPaintInvalidation())
-            container = compositingLayer->renderer();
-    }
+    if (RenderLayer* compositingLayer = enclosingLayer()->enclosingLayerForPaintInvalidationCrossingFrameBoundaries())
+        container = compositingLayer->renderer();
     return container;
 }
 
@@ -1508,14 +1506,12 @@ void RenderObject::invalidatePaintUsingContainer(const RenderLayerModelObject* p
         return;
     }
 
-    RenderView* v = view();
     if (paintInvalidationContainer->isRenderView()) {
-        ASSERT(paintInvalidationContainer == v);
-        v->invalidatePaintForRectangle(r);
+        toRenderView(paintInvalidationContainer)->invalidatePaintForRectangle(r);
         return;
     }
 
-    if (v->usesCompositing()) {
+    if (view()->usesCompositing()) {
         ASSERT(paintInvalidationContainer->hasLayer() && (paintInvalidationContainer->layer()->compositingState() == PaintsIntoOwnBacking || paintInvalidationContainer->layer()->compositingState() == PaintsIntoGroupedBacking));
         paintInvalidationContainer->layer()->repainter().setBackingNeedsRepaintInRect(r);
     }