[compositorworker] compositor proxy mutation updates underlying layers

third_party/WebKit/Source/web/CompositorProxyClientImpl.cpp

 // Copyright 2015 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/CompositorProxyClientImpl.h"
 
 #include "core/dom/CompositorProxy.h"
 #include "modules/compositorworker/CompositorWorkerGlobalScope.h"
 #include "platform/TraceEvent.h"
+#include "platform/graphics/CompositorMutableStateProvider.h"
 #include "web/CompositorMutatorImpl.h"
 #include "wtf/CurrentTime.h"
 
 namespace blink {
 
+// A helper class that updates proxies mutable state on creation and reset it
+// on destruction. This can be used with rAF callback to ensure no mutation is
+// allowed outside rAF.
+class ScopedCompositorMutableState final {
+    WTF_MAKE_NONCOPYABLE(ScopedCompositorMutableState);
+    STACK_ALLOCATED();
+public:
+    ScopedCompositorMutableState(HeapHashSet<WeakMember<CompositorProxy>>& proxies, CompositorMutableStateProvider* stateProvider)
+        : m_proxies(proxies)
+    {
+        for (CompositorProxy* proxy : m_proxies)
+            proxy->takeCompositorMutableState(stateProvider->getMutableStateFor(proxy->elementId()));
+
+    }
+    ~ScopedCompositorMutableState()
+    {
+        for (CompositorProxy* proxy : m_proxies)
+            proxy->takeCompositorMutableState(nullptr);
+    }
+private:
+    HeapHashSet<WeakMember<CompositorProxy>>& m_proxies;
+};
+
 CompositorProxyClientImpl::CompositorProxyClientImpl(CompositorMutatorImpl* mutator)
     : m_mutator(mutator)
     , m_globalScope(nullptr)
 {
 }
 
 DEFINE_TRACE(CompositorProxyClientImpl)
 {
     CompositorProxyClient::trace(visitor);
     visitor->trace(m_mutator);
@@ skipping 10 matching lines @@
     m_mutator->registerProxyClient(this);
 }
 
 void CompositorProxyClientImpl::requestAnimationFrame()
 {
     TRACE_EVENT0("compositor-worker", "CompositorProxyClientImpl::requestAnimationFrame");
     m_requestedAnimationFrameCallbacks = true;
     m_mutator->setNeedsMutate();
 }
 
-bool CompositorProxyClientImpl::mutate(double monotonicTimeNow)
+bool CompositorProxyClientImpl::mutate(double monotonicTimeNow, CompositorMutableStateProvider* stateProvider)
 {
     if (!m_globalScope)
         return false;
 
     TRACE_EVENT0("compositor-worker", "CompositorProxyClientImpl::mutate");
     if (!m_requestedAnimationFrameCallbacks)
         return false;
 
-    m_requestedAnimationFrameCallbacks = executeAnimationFrameCallbacks(monotonicTimeNow);
+    {
+        ScopedCompositorMutableState mutableState(m_proxies, stateProvider);
+        m_requestedAnimationFrameCallbacks = executeAnimationFrameCallbacks(monotonicTimeNow);
+    }
 
     return m_requestedAnimationFrameCallbacks;
 }
 
 bool CompositorProxyClientImpl::executeAnimationFrameCallbacks(double monotonicTimeNow)
 {
     TRACE_EVENT0("compositor-worker", "CompositorProxyClientImpl::executeAnimationFrameCallbacks");
+
     // Convert to zero based document time in milliseconds consistent with requestAnimationFrame.
     double highResTimeMs = 1000.0 * (monotonicTimeNow - m_globalScope->timeOrigin());
-    const bool shouldReinvoke = m_globalScope->executeAnimationFrameCallbacks(highResTimeMs);
-    return shouldReinvoke;
+    return m_globalScope->executeAnimationFrameCallbacks(highResTimeMs);
 }
 
 void CompositorProxyClientImpl::registerCompositorProxy(CompositorProxy* proxy)
 {
     m_proxies.add(proxy);
 }
 
 void CompositorProxyClientImpl::unregisterCompositorProxy(CompositorProxy* proxy)
 {
     m_proxies.remove(proxy);
 }
 
 } // namespace blink