compositor-worker: Force elements to grow a layer when a CompositorProxy is created.

Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 933 matching lines @@
     double scaledTop = view->scrollPositionDouble().y();
     if (scrollToOptions.hasLeft())
         scaledLeft = scrollToOptions.left() * frame->pageZoomFactor();
     if (scrollToOptions.hasTop())
         scaledTop = scrollToOptions.top() * frame->pageZoomFactor();
     view->setScrollPosition(DoublePoint(scaledLeft, scaledTop), scrollBehavior);
 }
 
 void Element::incrementProxyCount()
 {
-    ensureElementRareData().incrementProxyCount();
+    if (ensureElementRareData().incrementProxyCount() == 1)
+        setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::CompositorProxy));
 }
 
 void Element::decrementProxyCount()
 {
-    ensureElementRareData().decrementProxyCount();
+    if (ensureElementRareData().decrementProxyCount() == 0)
+        setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::CompositorProxy));
 }
 
 IntRect Element::boundsInViewportSpace()
 {
     document().updateLayoutIgnorePendingStylesheets();
 
     FrameView* view = document().view();
     if (!view)
         return IntRect();
 
@@ skipping 674 matching lines @@
     if (ElementAnimations* elementAnimations = this->elementAnimations()) {
         elementAnimations->cssAnimations().maybeApplyPendingUpdate(this);
         elementAnimations->updateAnimationFlags(*style);
     }
 
     if (style->hasTransform()) {
         if (const StylePropertySet* inlineStyle = this->inlineStyle())
             style->setHasInlineTransform(inlineStyle->hasProperty(CSSPropertyTransform) || inlineStyle->hasProperty(CSSPropertyWebkitTransform));
     }
 
+    if (hasRareData() && elementRareData()->proxyCount() > 0)
+        style->setHasCompositorProxy(true);
+
     document().didRecalculateStyleForElement();
     return style.release();
 }
 
 PassRefPtr<ComputedStyle> Element::originalStyleForLayoutObject()
 {
     ASSERT(document().inStyleRecalc());
     return document().ensureStyleResolver().styleForElement(this);
 }
 
@@ skipping 1842 matching lines @@
 {
 #if ENABLE(OILPAN)
     if (hasRareData())
         visitor->trace(elementRareData());
     visitor->trace(m_elementData);
 #endif
     ContainerNode::trace(visitor);
 }
 
 } // namespace blink