Reland Fix leak of RTCPeerConnectionHandler if PeerConnection.close() is called from js.…

content/renderer/media/mock_peer_connection_impl.h

Index: content/renderer/media/mock_peer_connection_impl.h
diff --git a/content/renderer/media/mock_peer_connection_impl.h b/content/renderer/media/mock_peer_connection_impl.h
index ef7d63bee5b4d7733a7a8e771d5a2871521e5558..2787b99b0561fd8dc36c10f2ec91efef01fda622 100644
--- a/content/renderer/media/mock_peer_connection_impl.h
+++ b/content/renderer/media/mock_peer_connection_impl.h
@@ -61,9 +61,8 @@ class MockPeerConnectionImpl : public webrtc::PeerConnectionInterface {
     NOTIMPLEMENTED();
     return PeerConnectionInterface::kIceGatheringNew;
   }
-  void Close() override {
-    NOTIMPLEMENTED();
-  }
+
+  MOCK_METHOD0(Close, void());
 
   const webrtc::SessionDescriptionInterface* local_description() const override;
   const webrtc::SessionDescriptionInterface* remote_description()