compositor-worker: Keep worker backing thread alive for the lifetime of the compositor thread.

third_party/WebKit/Source/modules/compositorworker/CompositorWorker.cpp

Index: third_party/WebKit/Source/modules/compositorworker/CompositorWorker.cpp
diff --git a/third_party/WebKit/Source/modules/compositorworker/CompositorWorker.cpp b/third_party/WebKit/Source/modules/compositorworker/CompositorWorker.cpp
index 3eefc6ac2809d657c9ed86b7a22aaaa1ff712249..86377397e51e93a8fd6c8013a280bb16af92fd8f 100644
--- a/third_party/WebKit/Source/modules/compositorworker/CompositorWorker.cpp
+++ b/third_party/WebKit/Source/modules/compositorworker/CompositorWorker.cpp
@@ -10,6 +10,7 @@
 #include "core/workers/WorkerClients.h"
 #include "modules/EventTargetModules.h"
 #include "modules/compositorworker/CompositorWorkerMessagingProxy.h"
+#include "modules/compositorworker/CompositorWorkerThread.h"
 
 namespace blink {
 
@@ -20,6 +21,11 @@ inline CompositorWorker::CompositorWorker(ExecutionContext* context)
 
 CompositorWorker* CompositorWorker::create(ExecutionContext* context, const String& url, ExceptionState& exceptionState)
 {
+    // Ensure the compositor worker backing thread is ready before we try to
+    // initialize the CompositorWorker so that we can construct oilpan
+    // objects on the compositor thread referenced from the worker clients.
+    CompositorWorkerThread::ensureSharedBackingThread();

[haraken, 2016/05/11 00:18:31]

Sorry for not being clear: I'm suggesting to move this to *just before* the
worker->initialize().

[flackr, 2016/05/18 05:26:50]

Ah, my apologies. Done.

+
     ASSERT(isMainThread());
     Document* document = toDocument(context);
     if (!document->page()) {