VideoCaptureDeviceAndroid: add ThreadChecker, lock access to |client_|, mini cleanup

media/capture/video/android/video_capture_device_android.h

 // Copyright (c) 2013 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_CAPTURE_VIDEO_ANDROID_VIDEO_CAPTURE_DEVICE_ANDROID_H_
 #define MEDIA_CAPTURE_VIDEO_ANDROID_VIDEO_CAPTURE_DEVICE_ANDROID_H_
 
 #include <jni.h>
 #include <string>
 
 #include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread.h"
+#include "base/threading/thread_checker.h"
 #include "base/time/time.h"
 #include "media/capture/capture_export.h"
 #include "media/capture/video/video_capture_device.h"
 
 namespace tracked_objects {
 class Location;
 }  // namespace tracked_
 
 namespace media {
 
@@ skipping 71 matching lines @@
   enum InternalState {
     kIdle,       // The device is opened but not in use.
     kCapturing,  // Video is being captured.
     kError       // Hit error. User needs to recover by destroying the object.
   };
 
   VideoPixelFormat GetColorspace();
   void SetErrorState(const tracked_objects::Location& from_here,
                      const std::string& reason);
 
+  base::ThreadChecker thread_checker_;
+
   // Prevent racing on accessing |state_| and |client_| since both could be
   // accessed from different threads.
   base::Lock lock_;
   InternalState state_;
+  std::unique_ptr<VideoCaptureDevice::Client> client_;
+
   bool got_first_frame_;
   base::TimeTicks expected_next_frame_time_;
   base::TimeTicks first_ref_time_;
   base::TimeDelta frame_interval_;
-  std::unique_ptr<VideoCaptureDevice::Client> client_;
 
   // List of |photo_callbacks_| in flight, being served in Java side.
   base::Lock photo_callbacks_lock_;
   std::list<std::unique_ptr<TakePhotoCallback>> photo_callbacks_;
 
   gfx::Size next_photo_resolution_;
 
   Name device_name_;
   VideoCaptureFormat capture_format_;
 
   // Java VideoCaptureAndroid instance.
   base::android::ScopedJavaLocalRef<jobject> j_capture_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceAndroid);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_CAPTURE_VIDEO_ANDROID_VIDEO_CAPTURE_DEVICE_ANDROID_H_