Revert of Removed unused cricket::VideoCapturer methods

webrtc/media/base/capturemanager.cc

 /*
  *  Copyright (c) 2012 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 179 matching lines @@
   if (!capture_state->RemoveCaptureResolution(format)) {
     return false;
   }
 
   if (capture_state->DecCaptureStartRef() == 0) {
     // Unregistering cannot fail as capture_state is not NULL.
     UnregisterVideoCapturer(capture_state);
   }
   return true;
 }
+
+bool CaptureManager::RestartVideoCapture(
+    VideoCapturer* video_capturer,
+    const VideoFormat& previous_format,
+    const VideoFormat& desired_format,
+    CaptureManager::RestartOptions options) {
+  RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  if (!IsCapturerRegistered(video_capturer)) {
+    LOG(LS_ERROR) << "RestartVideoCapture: video_capturer is not registered.";
+    return false;
+  }
+  // Start the new format first. This keeps the capturer running.
+  if (!StartVideoCapture(video_capturer, desired_format)) {
+    LOG(LS_ERROR) << "RestartVideoCapture: unable to start video capture with "
+        "desired_format=" << desired_format.ToString();
+    return false;
+  }
+  // Stop the old format.
+  if (!StopVideoCapture(video_capturer, previous_format)) {
+    LOG(LS_ERROR) << "RestartVideoCapture: unable to stop video capture with "
+        "previous_format=" << previous_format.ToString();
+    // Undo the start request we just performed.
+    StopVideoCapture(video_capturer, desired_format);
+    return false;
+  }
+
+  switch (options) {
+    case kForceRestart: {
+      VideoCapturerState* capture_state = GetCaptureState(video_capturer);
+      ASSERT(capture_state && capture_state->start_count() > 0);
+      // Try a restart using the new best resolution.
+      VideoFormat highest_asked_format =
+          capture_state->GetHighestFormat(video_capturer);
+      VideoFormat capture_format;
+      if (video_capturer->GetBestCaptureFormat(highest_asked_format,
+                                               &capture_format)) {
+        if (!video_capturer->Restart(capture_format)) {
+          LOG(LS_ERROR) << "RestartVideoCapture: Restart failed.";
+        }
+      } else {
+        LOG(LS_WARNING)
+            << "RestartVideoCapture: Couldn't find a best capture format for "
+            << highest_asked_format.ToString();
+      }
+      break;
+    }
+    case kRequestRestart:
+      // TODO(ryanpetrie): Support restart requests. Should this
+      // to-be-implemented logic be used for {Start,Stop}VideoCapture as well?
+      break;
+    default:
+      LOG(LS_ERROR) << "Unknown/unimplemented RestartOption";
+      break;
+  }
+  return true;
+}
 
 void CaptureManager::AddVideoSink(VideoCapturer* video_capturer,
                                   rtc::VideoSinkInterface<VideoFrame>* sink) {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
   // TODO(nisse): Do we really need to tolerate NULL inputs?
   if (!video_capturer || !sink) {
     return;
   }
   rtc::VideoSinkWants wants;
   // Renderers must be able to apply rotation.
@@ skipping 80 matching lines @@
     VideoCapturer* video_capturer) const {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
   CaptureStates::const_iterator iter = capture_states_.find(video_capturer);
   if (iter == capture_states_.end()) {
     return NULL;
   }
   return iter->second;
 }
 
 }  // namespace cricket