Introduce a basic Blink Scheduler

public/platform/WebScheduler.h

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  * Copyright (C) 2014 Google Inc. All rights reserved.
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@@ skipping 10 matching lines @@
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-#ifndef StorageQuotaClientImpl_h
-#define StorageQuotaClientImpl_h
+#ifndef WebScheduler_h
+#define WebScheduler_h
 
-#include "modules/quota/StorageQuotaClient.h"
-#include "wtf/Forward.h"
+#include "WebThread.h"
+
+namespace WebCore {
+class Scheduler;
+}
 
 namespace blink {
 
-class StorageQuotaClientImpl : public NoBaseWillBeGarbageCollectedFinalized<StorageQuotaClientImpl>, public WebCore::StorageQuotaClient {
-    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(StorageQuotaClientImpl);
+class WebScheduler {
 public:
-    static PassOwnPtrWillBeRawPtr<StorageQuotaClientImpl> create();
+    BLINK_PLATFORM_EXPORT ~WebScheduler();
 
-    virtual ~StorageQuotaClientImpl();
+    BLINK_PLATFORM_EXPORT static WebScheduler create();
 
-    virtual void requestQuota(WebCore::ExecutionContext*, WebStorageQuotaType, unsigned long long newQuotaInBytes, PassOwnPtr<WebCore::StorageQuotaCallback>, PassOwnPtr<WebCore::StorageErrorCallback>) OVERRIDE;
-    virtual WebCore::ScriptPromise requestPersistentQuota(WebCore::ScriptState*, unsigned long long newQuotaInBytes) OVERRIDE;
+    // Schedule a generic task to be run on the blink main thread. Takes
+    // ownership of |Task|. Can be called from any thread.
+    BLINK_PLATFORM_EXPORT void postTask(WebThread::Task*);
 
-    virtual void trace(WebCore::Visitor* visitor) OVERRIDE { WebCore::StorageQuotaClient::trace(visitor); }
+    // Schedule an input processing task to be run on the blink main thread.
+    // Takes ownership of |Task|. Can be called from any thread.
+    BLINK_PLATFORM_EXPORT void postInputTask(WebThread::Task*);
+
+    // Schedule a compositor task to run on the blink main thread. Takes
+    // ownership of |Task|. Can be called from any thread.
+    // TODO: Use WebFrameTime.
+    BLINK_PLATFORM_EXPORT void postCompositorTask(WebThread::Task*);
+
+    // Schedule a BeginFrame task to run on the blink main thread. Takes
+    // ownership of |Task|. Can be called from any thread. Will maintain
+    // oredering with other compositor tasks.
+    // TODO: Use WebFrameTime.
+    BLINK_PLATFORM_EXPORT void postBeginFrameTask(WebThread::Task*, double frameTime, double deadline, double interval);

[mithro-old, 2014/07/08 10:38:11]

If I understand correctly (which I'm never sure with the code under cc/) than in
many cases the system currently roughly goes,
 <begin frame generated>
 (on impl thread) ImplThread::Scheduler
 (on impl thread) ThreadProxy::ScheduledActionSendBeginMainFrame
 (on main thread) ThreadProxy::BeginMainFrame
 (on main thread) LayerTreeHost::UpdateClientAnimations
 (on main thread) LayerTreeHostClient::Animate
 (on main thread) RenderWidgetCompositor::Animate
 (on main thread) WebWidget::animate

Where would the "postBeginFrameTask" function replace?

 
 private:
-    StorageQuotaClientImpl();
+    WebScheduler();
+
+    WebCore::Scheduler* m_scheduler;
 };
 
 } // namespace blink
 
-#endif // StorageQuotaClientImpl_h
+#endif // WebScheduler_h