Adds a WebPageScheduler and a WebFrameScheduler

public/platform/WebScheduler.h

 // Copyright 2014 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.
 
 #ifndef WebScheduler_h
 #define WebScheduler_h
 
 #include "WebCommon.h"
 #include "public/platform/WebTaskRunner.h"
 #include "public/platform/WebThread.h"
 
 namespace blink {
 
+class WebPageScheduler;
 class WebTraceLocation;
 
 // This class is used to submit tasks and pass other information from Blink to
 // the platform's scheduler.
 class BLINK_PLATFORM_EXPORT WebScheduler {
 public:
     virtual ~WebScheduler() { }
 
     // Called to prevent any more pending tasks from running. Must be called on
     // the associated WebThread.
@@ skipping 53 matching lines @@
     // |monotonicTime| is in the timebase of WTF::monotonicallyIncreasingTime().
     // Takes ownership of |WebThread::Task|. Can be called from any thread.
     virtual void postTimerTaskAt(const WebTraceLocation&, WebThread::Task*, double monotonicTime) {}
 
     // Returns a WebTaskRunner for loading tasks. Can be called from any thread.
     virtual WebTaskRunner* loadingTaskRunner() { return nullptr; }
 
     // Returns a WebTaskRunner for timer tasks. Can be called from any thread.
     virtual WebTaskRunner* timerTaskRunner() { return nullptr; }
 
+    // Creates a new WebPageScheduler. Must be called from the associated WebThread.
+    virtual WebPageScheduler* createPageScheduler() { return nullptr; }
+
     // Suspends the timer queue and increments the timer queue suspension count.
     // May only be called from the main thread.
     virtual void suspendTimerQueue() { }
 
     // Decrements the timer queue suspension count and re-enables the timer queue
     // if the suspension count is zero and the current scheduler policy allows it.
     virtual void resumeTimerQueue() { }
 
 #ifdef INSIDE_BLINK
     // Helpers for posting bound functions as tasks.
     typedef Function<void(double deadlineSeconds)> IdleTask;
     typedef Function<void()> Task;
 
     void postIdleTask(const WebTraceLocation&, PassOwnPtr<IdleTask>);
     void postNonNestableIdleTask(const WebTraceLocation&, PassOwnPtr<IdleTask>);
     void postIdleTaskAfterWakeup(const WebTraceLocation&, PassOwnPtr<IdleTask>);
     void postLoadingTask(const WebTraceLocation&, PassOwnPtr<Task>);
     void postTimerTask(const WebTraceLocation&, PassOwnPtr<Task>, long long delayMs);
 #endif
 };
 
 } // namespace blink
 
 #endif // WebScheduler_h