Revert of Removed unused cricket::VideoCapturer methods

webrtc/media/base/videocapturer.h

Index: webrtc/media/base/videocapturer.h
diff --git a/webrtc/media/base/videocapturer.h b/webrtc/media/base/videocapturer.h
index b904582d8885bc24ea46616a16f35c98950c7c2b..543af026c04f25423a79d8d309cd7f35a019acd2 100644
--- a/webrtc/media/base/videocapturer.h
+++ b/webrtc/media/base/videocapturer.h
@@ -20,11 +20,12 @@
 #include "webrtc/base/basictypes.h"
 #include "webrtc/base/criticalsection.h"
 #include "webrtc/media/base/videosourceinterface.h"
+#include "webrtc/base/messagehandler.h"
 #include "webrtc/base/rollingaccumulator.h"
 #include "webrtc/base/scoped_ptr.h"
 #include "webrtc/base/sigslot.h"
+#include "webrtc/base/thread.h"
 #include "webrtc/base/timing.h"
-#include "webrtc/base/thread_checker.h"
 #include "webrtc/media/base/mediachannel.h"
 #include "webrtc/media/base/videoadapter.h"
 #include "webrtc/media/base/videobroadcaster.h"
@@ -36,6 +37,8 @@
 namespace cricket {
 
 // Current state of the capturer.
+// TODO(hellner): CS_NO_DEVICE is an error code not a capture state. Separate
+//                error codes and states.
 enum CaptureState {
   CS_STOPPED,    // The capturer has been stopped or hasn't started yet.
   CS_STARTING,   // The capturer is in the process of starting. Note, it may
@@ -44,6 +47,7 @@
                  // capturing.
   CS_PAUSED,     // The capturer has been paused.
   CS_FAILED,     // The capturer failed to start.
+  CS_NO_DEVICE,  // The capturer has no device and consequently failed to start.
 };
 
 class VideoFrame;
@@ -87,13 +91,13 @@
 // The captured frames may need to be adapted (for example, cropping).
 // Video adaptation is built into and enabled by default. After a frame has
 // been captured from the device, it is sent to the video adapter, then out to
-// the sinks.
+// the encoder.
 //
 // Programming model:
 //   Create an object of a subclass of VideoCapturer
 //   Initialize
 //   SignalStateChange.connect()
-//   AddOrUpdateSink()
+//   SignalFrameCaptured.connect()
 //   Find the capture format for Start() by either calling GetSupportedFormats()
 //   and selecting one of the supported or calling GetBestCaptureFormat().
 //   video_adapter()->OnOutputFormatRequest(desired_encoding_format)
@@ -107,10 +111,13 @@
 //   thread safe.
 //
 class VideoCapturer : public sigslot::has_slots<>,
+                      public rtc::MessageHandler,
                       public rtc::VideoSourceInterface<cricket::VideoFrame> {
  public:
+  // All signals are marshalled to |thread| or the creating thread if
+  // none is provided.
   VideoCapturer();
-
+  explicit VideoCapturer(rtc::Thread* thread);
   virtual ~VideoCapturer() {}
 
   // Gets the id of the underlying device, which is available after the capturer
@@ -156,6 +163,12 @@
   //   CS_FAILED:    if the capturer failes to start..
   //   CS_NO_DEVICE: if the capturer has no device and fails to start.
   virtual CaptureState Start(const VideoFormat& capture_format) = 0;
+  // Sets the desired aspect ratio. If the capturer is capturing at another
+  // aspect ratio it will crop the width or the height so that asked for
+  // aspect ratio is acheived. Note that ratio_w and ratio_h do not need to be
+  // relatively prime.
+  void UpdateAspectRatio(int ratio_w, int ratio_h);
+  void ClearAspectRatio();
 
   // Get the current capture format, which is set by the Start() call.
   // Note that the width and height of the captured frames may differ from the
@@ -165,10 +178,23 @@
     return capture_format_.get();
   }
 
+  // Pause the video capturer.
+  virtual bool Pause(bool paused);
   // Stop the video capturer.
   virtual void Stop() = 0;
   // Check if the video capturer is running.
   virtual bool IsRunning() = 0;
+  // Restart the video capturer with the new |capture_format|.
+  // Default implementation stops and starts the capturer.
+  virtual bool Restart(const VideoFormat& capture_format);
+  // TODO(thorcarpenter): This behavior of keeping the camera open just to emit
+  // black frames is a total hack and should be fixed.
+  // When muting, produce black frames then pause the camera.
+  // When unmuting, start the camera. Camera starts unmuted.
+  virtual bool MuteToBlackThenPause(bool muted);
+  virtual bool IsMuted() const {
+    return muted_;
+  }
   CaptureState capture_state() const {
     return capture_state_;
   }
@@ -191,6 +217,14 @@
   }
   bool enable_camera_list() {
     return enable_camera_list_;
+  }
+
+  // Enable scaling to ensure square pixels.
+  void set_square_pixel_aspect_ratio(bool square_pixel_aspect_ratio) {
+    square_pixel_aspect_ratio_ = square_pixel_aspect_ratio;
+  }
+  bool square_pixel_aspect_ratio() {
+    return square_pixel_aspect_ratio_;
   }
 
   // Signal all capture state changes that are not a direct result of calling
@@ -254,6 +288,9 @@
 
   void SetCaptureState(CaptureState state);
 
+  // Marshals SignalStateChange onto thread_.
+  void OnMessage(rtc::Message* message) override;
+
   // subclasses override this virtual method to provide a vector of fourccs, in
   // order of preference, that are expected by the media engine.
   virtual bool GetPreferredFourccs(std::vector<uint32_t>* fourccs) = 0;
@@ -302,7 +339,7 @@
       const rtc::RollingAccumulator<T>& data,
       VariableInfo<T>* stats);
 
-  rtc::ThreadChecker thread_checker_;
+  rtc::Thread* thread_;
   std::string id_;
   CaptureState capture_state_;
   rtc::scoped_ptr<VideoFrameFactory> frame_factory_;
@@ -317,6 +354,8 @@
   bool square_pixel_aspect_ratio_;  // Enable scaling to square pixels.
   int scaled_width_;  // Current output size from ComputeScale.
   int scaled_height_;
+  bool muted_;
+  int black_frame_count_down_;
 
   rtc::VideoBroadcaster broadcaster_;
   bool enable_video_adapter_;