Clean up ownership of webrtc::VideoEncoder

webrtc/media/engine/scopedvideoencoder.h

Index: webrtc/media/engine/scopedvideoencoder.h
diff --git a/webrtc/media/engine/scopedvideoencoder.h b/webrtc/media/engine/scopedvideoencoder.h
new file mode 100644
index 0000000000000000000000000000000000000000..f0ff40fd10eee827dee729965d4973bb7ffa75f9
--- /dev/null
+++ b/webrtc/media/engine/scopedvideoencoder.h
@@ -0,0 +1,33 @@
+/*
+ *  Copyright (c) 2017 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.
+ */
+
+#ifndef WEBRTC_MEDIA_ENGINE_SCOPEDVIDEOENCODER_H_
+#define WEBRTC_MEDIA_ENGINE_SCOPEDVIDEOENCODER_H_
+
+#include <memory>
+
+#include "webrtc/media/engine/webrtcvideoencoderfactory.h"
+
+namespace cricket {
+
+// Helper function that creates a webrtc::VideoEncoder held by an
+// std::unique_ptr instead of having to be deleted through
+// WebRtcVideoEncoderFactory::DestroyVideoEncoder. The factory passed in must
+// outlive the returned encoder.
+// TODO(magjed): This helper function will be deleted once
+// cricket::WebRtcVideoEncoderFactory is deprecated, see
+// https://bugs.chromium.org/p/webrtc/issues/detail?id=7925 for more info.
+std::unique_ptr<webrtc::VideoEncoder> CreateScopedVideoEncoder(
+    cricket::WebRtcVideoEncoderFactory* factory,
+    const VideoCodec& codec);
+
+}  // namespace cricket
+
+#endif  // WEBRTC_MEDIA_ENGINE_SCOPEDVIDEOENCODER_H_