android: Don't do a thread jump for incoming frames.

webrtc/api/androidvideocapturer.cc

 /*
  *  Copyright 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 162 matching lines @@
   if (new_state == current_state_)
     return;
   current_state_ = new_state;
   SetCaptureState(new_state);
 }
 
 void AndroidVideoCapturer::OnIncomingFrame(
     const rtc::scoped_refptr<webrtc::VideoFrameBuffer>& buffer,
     int rotation,
     int64_t time_stamp) {
-  RTC_CHECK(thread_checker_.CalledOnValidThread());
+  // NOTE: Calls to this method may come on any thread, but they are

[magjed_webrtc, 2016/05/18 15:12:50]

They come from the Java thread. It's the same thread every time, if that helps.

[nisse-webrtc, 2016/05/18 15:31:31]

Should be ok, then. Would it make sense with a thread checker to back that up?

+  // syncronized by the caller, using
+  // AndroidVideoCapturerJni:capturer_lock_.
   frame_factory_->UpdateCapturedFrame(buffer, rotation, time_stamp);
   SignalFrameCaptured(this, frame_factory_->GetCapturedFrame());
   frame_factory_->ClearCapturedFrame();
 }
 
 void AndroidVideoCapturer::OnOutputFormatRequest(
     int width, int height, int fps) {
   RTC_CHECK(thread_checker_.CalledOnValidThread());
   cricket::VideoFormat format(width, height,
                               cricket::VideoFormat::FpsToInterval(fps), 0);
   video_adapter()->OnOutputFormatRequest(format);
 }
 
 bool AndroidVideoCapturer::GetBestCaptureFormat(
     const cricket::VideoFormat& desired,
     cricket::VideoFormat* best_format) {
   // Delegate this choice to VideoCapturer.startCapture().
   *best_format = desired;
   return true;
 }
 
 }  // namespace webrtc