[S.P.] Don't draw frames of animated images that are offscreen

Source/core/layout/LayoutBoxModelObject.cpp

Index: Source/core/layout/LayoutBoxModelObject.cpp
diff --git a/Source/core/layout/LayoutBoxModelObject.cpp b/Source/core/layout/LayoutBoxModelObject.cpp
index 7f7e52dab4b00821c2d0e9d6cc0a33e551e49f5e..2120abb9912c64bf0ad7cea98465e2e5de033c82 100644
--- a/Source/core/layout/LayoutBoxModelObject.cpp
+++ b/Source/core/layout/LayoutBoxModelObject.cpp
@@ -264,7 +264,12 @@ void LayoutBoxModelObject::invalidateTreeIfNeeded(const PaintInvalidationState&
     // ASSERT(&newPaintInvalidationContainer == containerForPaintInvalidation());
 
     PaintInvalidationReason reason = invalidatePaintIfNeeded(paintInvalidationState, newPaintInvalidationContainer);
-    clearPaintInvalidationState(paintInvalidationState);
+    if (reason != PaintInvalidationDelayedFull) {
+        clearPaintInvalidationState(paintInvalidationState);
+    } else {
+        // Mark this object as needing paint invalidation again in the next frame, due to the request for delayed paint invalidation.
+        setShouldDoFullPaintInvalidation(reason);

[esprehn, 2015/03/25 05:06:36]

This doesn't seem right from inside the invalidateTreeIfNeeded walk, I think you
want to push these into a separate vector and invalidate after the primary walk.

[chrishtr, 2015/03/25 23:30:35]

That's a good idea, and as you pointed out elsewhere makes the code safer. Done.

+    }
 
     PaintInvalidationState childTreeWalkState(paintInvalidationState, *this, newPaintInvalidationContainer);
     if (reason == PaintInvalidationLocationChange)