compositor-worker: Add CompositorProxyClient worker client of CompositorWorker.

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

Index: third_party/WebKit/Source/modules/compositorworker/CompositorWorkerGlobalScope.cpp
diff --git a/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerGlobalScope.cpp b/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerGlobalScope.cpp
index 38f958c7f366a1c3106d8af1cb3f3323c277d9be..9da21466581f5046a8a34fed727ae44663be836c 100644
--- a/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerGlobalScope.cpp
+++ b/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerGlobalScope.cpp
@@ -24,8 +24,10 @@ CompositorWorkerGlobalScope* CompositorWorkerGlobalScope::create(CompositorWorke
 
 CompositorWorkerGlobalScope::CompositorWorkerGlobalScope(const KURL& url, const String& userAgent, CompositorWorkerThread* thread, double timeOrigin, PassOwnPtr<SecurityOrigin::PrivilegeData> starterOriginPrivilegeData, WorkerClients* workerClients)
     : WorkerGlobalScope(url, userAgent, thread, timeOrigin, std::move(starterOriginPrivilegeData), workerClients)
+    , m_executingAnimationFrameCallbacks(false)
     , m_callbackCollection(this)
 {
+    CompositorProxyClient::from(clients())->setGlobalScope(this);
 }
 
 CompositorWorkerGlobalScope::~CompositorWorkerGlobalScope()
@@ -54,6 +56,10 @@ void CompositorWorkerGlobalScope::postMessage(ExecutionContext* executionContext
 
 int CompositorWorkerGlobalScope::requestAnimationFrame(FrameRequestCallback* callback)
 {
+    // For now, just post a task to call mutate on the compositor proxy client.

[jbroman, 2016/05/09 18:44:18]

Please leave a more strongly-worded TODO here so it's obvious this is a super
temporary measure. Something like:

// TODO(flackr): Remove this when ____________________.

[flackr, 2016/05/10 20:56:13]

Done.

+    thread()->postTask(BLINK_FROM_HERE, createSameThreadTask(&CompositorProxyClient::triggerMutationForTest,

[kinuko, 2016/05/09 02:41:26]

invoking test-only method from web-facing API and having all these code in
production code looks weird to me...

[flackr, 2016/05/10 20:56:13]

You're right, let's just remove the ForTest and call this something more
meaningful. This is our workaround for being able to test this path when we're
not able to actually request frames from the compositor. Done.

+        CompositorProxyClient::from(clients())));
+    // TODO(flackr): Signal the compositor to call mutate on the next compositor frame.
     return m_callbackCollection.registerCallback(callback);
 }
 
@@ -62,9 +68,11 @@ void CompositorWorkerGlobalScope::cancelAnimationFrame(int id)
     m_callbackCollection.cancelCallback(id);
 }
 
-void CompositorWorkerGlobalScope::executeAnimationFrameCallbacks(double highResTimeNow)
+bool CompositorWorkerGlobalScope::executeAnimationFrameCallbacks(double highResTimeMs)
 {
-    m_callbackCollection.executeCallbacks(highResTimeNow, highResTimeNow);
+    TemporaryChange<bool> temporaryChange(m_executingAnimationFrameCallbacks, true);
+    m_callbackCollection.executeCallbacks(highResTimeMs, highResTimeMs);
+    return !m_callbackCollection.isEmpty();
 }
 
 CompositorWorkerThread* CompositorWorkerGlobalScope::thread() const