Add support for base::Closure in the MessageLoop.

content/gpu/gpu_watchdog_thread.h

Index: content/gpu/gpu_watchdog_thread.h
diff --git a/content/gpu/gpu_watchdog_thread.h b/content/gpu/gpu_watchdog_thread.h
index b0812a64d196dee5ca018ceeddd5fb5e84975e5f..fcf1b58b68e5a0a1a3e30fd597917dba5229c50a 100644
--- a/content/gpu/gpu_watchdog_thread.h
+++ b/content/gpu/gpu_watchdog_thread.h
@@ -32,14 +32,14 @@ class GpuWatchdogThread : public base::Thread,
 
   // An object of this type intercepts the reception and completion of all tasks
   // on the watched thread and checks whether the watchdog is armed.
-  class GpuWatchdogTaskObserver : public MessageLoop::TaskObserver {
+  class GpuWatchdogClosureObserver : public MessageLoop::ClosureObserver {
    public:
-    explicit GpuWatchdogTaskObserver(GpuWatchdogThread* watchdog);
-    virtual ~GpuWatchdogTaskObserver();
+    explicit GpuWatchdogClosureObserver(GpuWatchdogThread* watchdog);
+    virtual ~GpuWatchdogClosureObserver();
 
-    // Implements MessageLoop::TaskObserver.
-    virtual void WillProcessTask(const Task* task);
-    virtual void DidProcessTask(const Task* task);
+    // Implements MessageLoop::ClosureObserver.
+    virtual void WillProcessClosure(base::TimeTicks time_posted) OVERRIDE;
+    virtual void DidProcessClosure(base::TimeTicks time_posted) OVERRIDE;
 
    private:
     void CheckArmed();
@@ -56,7 +56,7 @@ class GpuWatchdogThread : public base::Thread,
   MessageLoop* watched_message_loop_;
   int timeout_;
   volatile bool armed_;
-  GpuWatchdogTaskObserver task_observer_;
+  GpuWatchdogClosureObserver closure_observer_;
 
 #if defined(OS_WIN)
   void* watched_thread_handle_;