Adding unit test to ensure TURN server priorities are unique.

talk/app/webrtc/peerconnection_unittest.cc

Index: talk/app/webrtc/peerconnection_unittest.cc
diff --git a/talk/app/webrtc/peerconnection_unittest.cc b/talk/app/webrtc/peerconnection_unittest.cc
index a2780a36e14ecd300c76c9ce37722a94be4b0392..8d0793e25f83f90e85f848e7277725490c707824 100644
--- a/talk/app/webrtc/peerconnection_unittest.cc
+++ b/talk/app/webrtc/peerconnection_unittest.cc
@@ -2022,4 +2022,17 @@ TEST_F(IceServerParsingTest, ParseMultipleUrls) {
   EXPECT_EQ(1U, turn_servers_.size());
 }
 
+// Ensure that TURN servers are given unique priorities,
+// so that their resulting candidates have unique priorities.
+TEST_F(IceServerParsingTest, TurnServerPrioritiesUnique) {
+  PeerConnectionInterface::IceServers servers;
+  PeerConnectionInterface::IceServer server;
+  server.urls.push_back("turn:hostname");
+  server.urls.push_back("turn:hostname2");
+  servers.push_back(server);
+  EXPECT_TRUE(webrtc::ParseIceServers(servers, &stun_servers_, &turn_servers_));
+  EXPECT_EQ(2U, turn_servers_.size());
+  EXPECT_NE(turn_servers_[0].priority, turn_servers_[1].priority);
+}
+
 #endif // if !defined(THREAD_SANITIZER)