[Mojo Video Capture] Add test coverage for accelerated jpeg decoding

media/capture/video/video_capture_device_client.h

Index: media/capture/video/video_capture_device_client.h
diff --git a/media/capture/video/video_capture_device_client.h b/media/capture/video/video_capture_device_client.h
index a1b298fe81e02769cc1d70f644823b6d7f80f6a1..875b27b58c0ce54ba09b6296167a47f0d53e8e91 100644
--- a/media/capture/video/video_capture_device_client.h
+++ b/media/capture/video/video_capture_device_client.h
@@ -85,6 +85,9 @@ class CAPTURE_EXPORT VideoCaptureDeviceClient
   double GetBufferPoolUtilization() const override;
 
  private:
+  void OnUsingExternalJpegDecoder();
+  void OnNotUsingExternalJpegDecoder();
+
   void InitializeI420PlanePointers(const gfx::Size& dimensions,
                                    uint8_t* const data,
                                    uint8_t** y_plane_data,
@@ -108,6 +111,7 @@ class CAPTURE_EXPORT VideoCaptureDeviceClient
 
   // Whether |external_jpeg_decoder_| has been initialized.
   bool external_jpeg_decoder_initialized_;
+  bool using_external_jpeg_decoder_;

[mcasas, 2017/03/07 19:39:38]

Isn't this variable having the same lifetime changes
as |external_jpeg_decoder_| ?  If so, you don't need
the extra methods.

[chfremer, 2017/03/07 22:30:38]

The |external_jpeg_decoder_| is created and initially exists with a status
INIT_PENDING. At some point after that it changes its state to INIT_PASSED. Only
then do we want to send OnStartedUsingGpuDecode() and we only want to send it
once. I don't see how to do it without the flag.

 
   // The pool of shared-memory buffers used for capturing.
   const scoped_refptr<VideoCaptureBufferPool> buffer_pool_;