Fix memory leak in VideoToolbox encoder.

webrtc/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoEncoderH264.mm

 /*
  *  Copyright (c) 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 646 matching lines @@
 
   if (isKeyframe) {
     LOG(LS_INFO) << "Generated keyframe";
   }
 
   // Convert the sample buffer into a buffer suitable for RTP packetization.
   // TODO(tkchin): Allocate buffers through a pool.
   std::unique_ptr<rtc::Buffer> buffer(new rtc::Buffer());
   RTCRtpFragmentationHeader *header;
   {
-    webrtc::RTPFragmentationHeader *header_cpp;
+    std::unique_ptr<webrtc::RTPFragmentationHeader> header_cpp;
     bool result =
         H264CMSampleBufferToAnnexBBuffer(sampleBuffer, isKeyframe, buffer.get(), &header_cpp);
-    header = [[RTCRtpFragmentationHeader alloc] initWithNativeFragmentationHeader:header_cpp];
+    header = [[RTCRtpFragmentationHeader alloc] initWithNativeFragmentationHeader:header_cpp.get()];
     if (!result) {
       return;
     }
   }
 
   RTCEncodedImage *frame = [[RTCEncodedImage alloc] init];
   frame.buffer = [NSData dataWithBytesNoCopy:buffer->data() length:buffer->size() freeWhenDone:NO];
   frame.encodedWidth = width;
   frame.encodedHeight = height;
   frame.completeFrame = YES;
@@ skipping 17 matching lines @@
   }
   _bitrateAdjuster->Update(frame.buffer.length);
 }
 
 - (RTCVideoEncoderQpThresholds *)scalingSettings {
   return [[RTCVideoEncoderQpThresholds alloc] initWithThresholdsLow:kLowH264QpThreshold
                                                                high:kHighH264QpThreshold];
 }
 
 @end