Centralize deferred commit conditions.

Source/core/dom/Document.h

Index: Source/core/dom/Document.h
diff --git a/Source/core/dom/Document.h b/Source/core/dom/Document.h
index 1a4f2e01aa4ad9f9b71e1ebd7aed5bcb0e31a2a1..96e20f72241a9861250a8c4c4f6b7215b9868736 100644
--- a/Source/core/dom/Document.h
+++ b/Source/core/dom/Document.h
@@ -908,6 +908,8 @@ public:
 
     const DocumentTiming& timing() const { return m_documentTiming; }
 
+    bool shouldProcessFrameLifecycle();
+
     int requestAnimationFrame(FrameRequestCallback*);
     void cancelAnimationFrame(int id);
     void serviceScriptedAnimations(double monotonicAnimationStartTime);
@@ -1144,6 +1146,7 @@ private:
 
     bool m_hasNodesWithPlaceholderStyle;
     bool m_evaluateMediaQueriesOnStyleRecalc;
+    bool m_shouldProcessFrameLifecycle;
 
     // If we do ignore the pending stylesheet count, then we need to add a boolean
     // to track that this happened so that we can do a full repaint when the stylesheets