Test field trial group with startswith rather than equals.

webrtc/media/engine/webrtcvideocapturer.cc

 /*
  *  Copyright (c) 2011 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 212 matching lines @@
                  << best_format->ToString();
   }
   return true;
 }
 void WebRtcVideoCapturer::OnSinkWantsChanged(const rtc::VideoSinkWants& wants) {
   // Can't take lock here as this will cause deadlock with
   // OnIncomingCapturedFrame. In fact, the whole method, including methods it
   // calls, can't take lock.
   RTC_DCHECK(module_);
 
-  const std::string group_name =
-      webrtc::field_trial::FindFullName("WebRTC-CVO");
-
-  if (group_name == "Disabled") {
+  if (webrtc::field_trial::FindFullName("WebRTC-CVO").find("Disabled") == 0)
     return;
-  }
 
   VideoCapturer::OnSinkWantsChanged(wants);
   bool result = module_->SetApplyRotation(wants.rotation_applied);
   RTC_CHECK(result);
 
   return;
 }
 
 CaptureState WebRtcVideoCapturer::Start(const VideoFormat& capture_format) {
   if (!module_) {
@@ skipping 96 matching lines @@
   if (1 == captured_frames_) {
     LOG(LS_INFO) << "Captured frame size "
                  << sample.width() << "x" << sample.height()
                  << ". Expected format " << GetCaptureFormat()->ToString();
   }
 
   VideoCapturer::OnFrame(sample, sample.width(), sample.height());
 }
 
 }  // namespace cricket