Interface RTCRtpReceiver and RTCPeerConnection.getReceivers() added.

third_party/WebKit/public/platform/WebRTCRtpReceiver.h

Index: third_party/WebKit/public/platform/WebRTCRtpReceiver.h
diff --git a/third_party/WebKit/public/platform/WebRTCRtpReceiver.h b/third_party/WebKit/public/platform/WebRTCRtpReceiver.h
new file mode 100644
index 0000000000000000000000000000000000000000..d41a5a6be0d0368c3287fa4ecb185a87ebd47e3b
--- /dev/null
+++ b/third_party/WebKit/public/platform/WebRTCRtpReceiver.h
@@ -0,0 +1,30 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef WebRTCRtpReceiver_h
+#define WebRTCRtpReceiver_h
+
+#include "WebCommon.h"
+#include "WebString.h"
+
+namespace blink {
+
+class WebMediaStreamTrack;
+
+// Implementations of this interface keep the corresponding WebRTC-layer
+// receiver alive through reference counting. Multiple |WebRTCRtpReceiver|s
+// could reference the same receiver, see |id|.
+class BLINK_PLATFORM_EXPORT WebRTCRtpReceiver {
+ public:
+  virtual ~WebRTCRtpReceiver();
+
+  // Two |WebRTCRtpReceiver|s referencing the same WebRTC-layer receiver have
+  // the same |id|.
+  virtual uintptr_t id() const = 0;
+  virtual const WebMediaStreamTrack& track() const = 0;
+};
+
+}  // namespace blink
+
+#endif  // WebRTCRtpReceiver_h