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 68aeea787efbd0df83e1536f27344baf5ff41bf9..fdf34910c70d6370aab80b9fed5e87be3b1d58fb 100644
--- a/content/gpu/gpu_watchdog_thread.h
+++ b/content/gpu/gpu_watchdog_thread.h
@@ -33,14 +33,14 @@ 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:
     GpuWatchdogThread* watchdog_;
@@ -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_;