Disable threaded compositing when texture sharing is blacklisted

webkit/compositor_bindings/web_compositor_support_impl.cc

Index: webkit/compositor_bindings/web_compositor_support_impl.cc
diff --git a/webkit/compositor_bindings/web_compositor_support_impl.cc b/webkit/compositor_bindings/web_compositor_support_impl.cc
index 32a18408180f2ff163223c1aac85fcc6eec1549f..6d237be7755e04f0cdf5d1ac6f6c45eb96759312 100644
--- a/webkit/compositor_bindings/web_compositor_support_impl.cc
+++ b/webkit/compositor_bindings/web_compositor_support_impl.cc
@@ -5,6 +5,7 @@
 #include "config.h"
 #include "webkit/compositor_bindings/web_compositor_support_impl.h"
 
+#include "base/debug/trace_event.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/settings.h"
 #include "webkit/compositor_bindings/web_animation_impl.h"
@@ -56,6 +57,9 @@ WebCompositorSupportImpl::~WebCompositorSupportImpl() {
 }
 
 void WebCompositorSupportImpl::initialize(WebKit::WebThread* thread) {
+  if (thread) {
+    TRACE_EVENT_INSTANT0("test_gpu", "ThreadedCompositingInitialization");
+  }
   WebCompositorImpl::initialize(thread);
 }