Cast: Added missing DCHECKs to ThreadChecker calls and minor cleanup.

media/cast/logging/simple_event_subscriber.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 MEDIA_CAST_LOGGING_SIMPLE_EVENT_SUBSCRIBER_H_
 #define MEDIA_CAST_LOGGING_SIMPLE_EVENT_SUBSCRIBER_H_
 
 #include <vector>
 
-#include "base/memory/ref_counted.h"
-#include "base/single_thread_task_runner.h"
 #include "base/threading/thread_checker.h"
 #include "media/cast/logging/raw_event_subscriber.h"
 
 namespace media {
 namespace cast {
 
 // RawEventSubscriber implementation that records all incoming raw events
 // in std::vector's.
 // The user of this class can call the GetXXXEventsAndReset functions to get
 // list of events that have acccumulated since last inovcation.
 class SimpleEventSubscriber : public RawEventSubscriber {
  public:
-  // |main_thread_proxy|: Only used for ensuring the subscriber is only called
-  // on the main thread. This object does not keep a reference on it.
-  explicit SimpleEventSubscriber(
-      const scoped_refptr<base::SingleThreadTaskRunner>& main_thread_proxy);
+  SimpleEventSubscriber();
 
   virtual ~SimpleEventSubscriber();
 
+  // RawEventSubscriber implementations.
   virtual void OnReceiveFrameEvent(const FrameEvent& frame_event) OVERRIDE;
-
   virtual void OnReceivePacketEvent(const PacketEvent& packet_event) OVERRIDE;
-
   virtual void OnReceiveGenericEvent(const GenericEvent& generic_event)
       OVERRIDE;
 
   // Assigns frame events received so far to |frame_events| and clears them
   // from this object.
   void GetFrameEventsAndReset(std::vector<FrameEvent>* frame_events);
 
   // Assigns packet events received so far to |packet_events| and clears them
   // from this object.
   void GetPacketEventsAndReset(std::vector<PacketEvent>* packet_events);
@@ skipping 10 matching lines @@
   // All functions must be called on the main thread.
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(SimpleEventSubscriber);
 };
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_LOGGING_SIMPLE_EVENT_SUBSCRIBER_H_