Defer starting of animations until after compositing update

Source/core/rendering/RenderLayerCompositor.cpp

Index: Source/core/rendering/RenderLayerCompositor.cpp
diff --git a/Source/core/rendering/RenderLayerCompositor.cpp b/Source/core/rendering/RenderLayerCompositor.cpp
index 4ea971ba77e2ad55d00844322edf4f4cfe838745..5900e0af1761ee74759fe79f0e102c1819fc6a3f 100644
--- a/Source/core/rendering/RenderLayerCompositor.cpp
+++ b/Source/core/rendering/RenderLayerCompositor.cpp
@@ -401,8 +401,17 @@ void RenderLayerCompositor::updateCompositingLayers()
         return;
 
     lifecycle().advanceTo(DocumentLifecycle::InCompositingUpdate);
-    DocumentLifecycle::Scope lifecycleScope(lifecycle(), DocumentLifecycle::CompositingClean);
 
+    updateCompositingLayersInternal();
+
+    lifecycle().advanceTo(DocumentLifecycle::CompositingClean);
+
+    DocumentAnimations::startPendingAnimations(m_renderView->document());
+    DocumentAnimations::dispatchAnimationEventsAsync(m_renderView->document());

[esprehn, 2014/02/24 23:14:35]

You should ASSERT() at the end that the lifecycle() is still at
CompositingClean, DocumentAnimations in here shouldn't be allowed to make the
state move backwards.

[dstockwell, 2014/02/25 00:52:03]

Done.

+}
+
+void RenderLayerCompositor::updateCompositingLayersInternal()
+{
     if (isMainFrame() && m_renderView->frameView())
         finishCompositingUpdateForFrameTree(&m_renderView->frameView()->frame());