compositor-worker: Initialize CW machinery plumbing to compositor and fire CW rAF callbacks.

third_party/WebKit/Source/web/CompositorMutatorImpl.cpp

Index: third_party/WebKit/Source/web/CompositorMutatorImpl.cpp
diff --git a/third_party/WebKit/Source/web/CompositorMutatorImpl.cpp b/third_party/WebKit/Source/web/CompositorMutatorImpl.cpp
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index 0000000000000000000000000000000000000000..e3c52ac299d794b93f11c6551117d36cf6f7d111
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+++ b/third_party/WebKit/Source/web/CompositorMutatorImpl.cpp
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+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "web/CompositorMutatorImpl.h"
+
+#include "core/animation/CustomCompositorAnimationManager.h"
+#include "core/dom/CompositorProxy.h"
+#include "platform/ThreadSafeFunctional.h"
+#include "platform/TraceEvent.h"
+#include "platform/WaitableEvent.h"
+#include "platform/graphics/CompositorMutationsTarget.h"
+#include "platform/graphics/CompositorMutatorClient.h"
+#include "platform/heap/Handle.h"
+#include "public/platform/Platform.h"
+#include "web/CompositorProxyClientImpl.h"
+
+namespace blink {
+
+namespace {
+
+void createCompositorMutatorClient(std::unique_ptr<CompositorMutatorClient>* ptr, WaitableEvent* doneEvent)
+{
+    CompositorMutatorImpl* mutator = CompositorMutatorImpl::create();
+    ptr->reset(new CompositorMutatorClient(mutator, mutator->animationManager()));
+    mutator->setClient(ptr->get());
+    doneEvent->signal();
+}
+
+} // namespace
+
+CompositorMutatorImpl::CompositorMutatorImpl()
+    : m_animationManager(adoptPtr(new CustomCompositorAnimationManager))
+    , m_client(nullptr)
+{
+}
+
+std::unique_ptr<CompositorMutatorClient> CompositorMutatorImpl::createClient()
+{
+    std::unique_ptr<CompositorMutatorClient> mutatorClient;
+    WaitableEvent doneEvent;
+    if (WebThread* compositorThread = Platform::current()->compositorThread()) {
+        compositorThread->getWebTaskRunner()->postTask(BLINK_FROM_HERE, threadSafeBind(&createCompositorMutatorClient, AllowCrossThreadAccess(&mutatorClient), AllowCrossThreadAccess(&doneEvent)));
+    } else {
+        createCompositorMutatorClient(&mutatorClient, &doneEvent);
+    }
+    // TODO(flackr): Instead of waiting for this event, we may be able to just set the
+    // mutator on the CompositorProxyClient directly from the compositor thread before
+    // it gets used there. We still need to make sure we only create one mutator though.
+    doneEvent.wait();
+    return mutatorClient;
+}
+
+CompositorMutatorImpl* CompositorMutatorImpl::create()
+{
+    return new CompositorMutatorImpl();
+}
+
+bool CompositorMutatorImpl::mutate(double monotonicTimeNow)
+{
+    TRACE_EVENT0("compositor-worker", "CompositorMutatorImpl::mutate");
+    bool needToReinvoke = false;
+    // TODO(vollick): we should avoid executing the animation frame
+    // callbacks if none of the proxies in the global scope are affected by
+    // m_mutations.
+    for (CompositorProxyClientImpl* client : m_proxyClients) {
+        if (client->mutate(monotonicTimeNow))
+            needToReinvoke = true;
+    }
+
+    return needToReinvoke;
+}
+
+void CompositorMutatorImpl::registerProxyClient(CompositorProxyClientImpl* client)
+{
+    TRACE_EVENT0("compositor-worker", "CompositorMutatorImpl::registerClient");
+    m_proxyClients.add(client);
+    setNeedsMutate();
+}
+
+void CompositorMutatorImpl::setNeedsMutate()
+{
+    TRACE_EVENT0("compositor-worker", "CompositorMutatorImpl::setNeedsMutate");
+    m_client->setNeedsMutate();
+}
+
+} // namespace blink