Replace RefCountImpl with rtc::RefCountedObject.

webrtc/test/vcm_capturer.cc

 /*
  *  Copyright (c) 2013 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 61 matching lines @@
   rtc::CritScope lock(&crit_);
   started_ = true;
 }
 
 void VcmCapturer::Stop() {
   rtc::CritScope lock(&crit_);
   started_ = false;
 }
 
 void VcmCapturer::Destroy() {
-  if (vcm_ == NULL) {
+  if (!vcm_)
     return;
-  }
 
   vcm_->StopCapture();
   vcm_->DeRegisterCaptureDataCallback();
-  vcm_->Release();
-
-  // TODO(pbos): How do I destroy the VideoCaptureModule? This still leaves

[tommi, 2016/03/17 09:15:12]

is this still true? (if so, please leave the comment in)

[pbos-webrtc, 2016/03/17 15:04:00]

Not true anymore, since the creation does AddRef() now the assignment Release()s
properly.

[tommi, 2016/03/17 15:10:56]

I'm not following... the previous code already did vcm_->Release(), what's
different?

[pbos-webrtc, 2016/03/21 10:04:31]

That it did not do AddRef() which is now done implicitly through the
scoped_refptr.

[tommi, 2016/03/21 11:23:21]

Oh I see!  Yikes, that could also be an invite to a use-after-free issue (e.g.
if someone else AddRef+Releases the object). Do you know if there are more cases
of this (specifically in non-test code)?

-  //             non-freed memory.
-  vcm_ = NULL;
+  // Release reference to VCM.
+  vcm_ = nullptr;
 }
 
 VcmCapturer::~VcmCapturer() { Destroy(); }
 
 void VcmCapturer::OnIncomingCapturedFrame(const int32_t id,
                                           const VideoFrame& frame) {
   rtc::CritScope lock(&crit_);
   if (started_)
     input_->IncomingCapturedFrame(frame);
 }
 
 void VcmCapturer::OnCaptureDelayChanged(const int32_t id, const int32_t delay) {
 }
 }  // test
 }  // webrtc