Don't schedule an animation during compositing dirty-bit setting unless needed.

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index c111f2c4bd18fec240b84fd55b0b9862c15f6f04..076cc6d46d7050c0368170909755e829ad3c5492 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -2788,8 +2788,14 @@ void FrameView::updateLayoutAndStyleForPainting()
     RefPtr<FrameView> protector(this);
 
     updateLayoutAndStyleIfNeededRecursive();
-    if (RenderView* view = renderView())
+    if (RenderView* view = renderView()) {
+        ASSERT(!view->needsLayout());
         view->compositor()->updateCompositingLayers();
+
+        // FIXME: we should not have any dirty bits left at this point. Unfortunately, this is not yet the case because
+        // the code in updateCompositingLayers sometimes creates new dirty bits when updating direct compositing reasons.
+        view->compositor()->scheduleAnimationIfNeeded();

[abarth-chromium, 2014/03/19 18:26:11]

Would you be willing to file a bug on this topic?  If there are unresolved dirty
bits, that means we'll put up a bad frame, right?

[chrishtr, 2014/03/19 18:31:14]

Done.

+    }
 }
 
 void FrameView::updateLayoutAndStyleIfNeededRecursive()