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

Source/core/dom/CompositorProxy.cpp

Index: Source/core/dom/CompositorProxy.cpp
diff --git a/Source/core/dom/CompositorProxy.cpp b/Source/core/dom/CompositorProxy.cpp
index f656b9c65e8563d7dfbbfc6f96e5640fb5c10f06..a8c11a519e0867821c8dd49123580a6be750502b 100644
--- a/Source/core/dom/CompositorProxy.cpp
+++ b/Source/core/dom/CompositorProxy.cpp
@@ -10,6 +10,7 @@
 #include "core/dom/DOMNodeIds.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/ExecutionContext.h"
+#include "core/style/ComputedStyle.h"
 
 namespace blink {
 
@@ -114,6 +115,9 @@ CompositorProxy::CompositorProxy(Element& element, const Vector<String>& attribu
     ASSERT(isMainThread());
     ASSERT(m_bitfieldsSupported);
     ASSERT(sanityCheckAttributeFlags(m_bitfieldsSupported));
+
+    element.setHasCompositorProxy(true);

[Ian Vollick, 2015/04/07 16:40:15]

Where do we set this to false?

[sadrul, 2015/04/07 16:43:23]

We currently do not. The API will need to have a CompositorProxy::disconnect().
If all the CompositorProxy objects for an element (both in the main-thread and
the worker-thread) die, or call disconnect(), then we can safely set this flag
back to false. I am working on that in a separate CL.

+    element.setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::CompositorProxy));
 }
 
 CompositorProxy::CompositorProxy(uint64_t elementId, uint32_t attributeFlags)