Fix the generation mismatch assertion error.

talk/app/webrtc/webrtcsession_unittest.cc

 /*
  * libjingle
  * Copyright 2012 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 2562 matching lines @@
   EXPECT_FALSE(session_->SetRemoteDescription(modified_offer, &error));
 
   sdp.clear();
   ModifyIceUfragPwdLines(offer.get(), kTooLongIceUfragPwd, kTooLongIceUfragPwd,
                          &sdp);
   modified_offer = CreateSessionDescription(JsepSessionDescription::kOffer, sdp,
                                             NULL);
   EXPECT_FALSE(session_->SetRemoteDescription(modified_offer, &error));
 }
 
+// Test that if the remote description indicates the peer requested ICE restart
+// (via a new ufrag or pwd), the old ICE candidates are not copied,
+// and vice versa.
+TEST_F(WebRtcSessionTest, TestSetRemoteDescriptionWithIceRestart) {
+  Init();
+  scoped_ptr<SessionDescriptionInterface> offer(CreateRemoteOffer());
+
+  // Create the first offer.
+  std::string sdp;
+  ModifyIceUfragPwdLines(offer.get(), "0123456789012345",
+                         "abcdefghijklmnopqrstuvwx", &sdp);
+  SessionDescriptionInterface* offer1 =
+      CreateSessionDescription(JsepSessionDescription::kOffer, sdp, NULL);
+  cricket::Candidate candidate1(1, "udp", rtc::SocketAddress("1.1.1.1", 5000),
+                                0, "", "", "relay", 0, "");
+  JsepIceCandidate ice_candidate1(kMediaContentName0, kMediaContentIndex0,
+                                  candidate1);
+  EXPECT_TRUE(offer1->AddCandidate(&ice_candidate1));
+  SetRemoteDescriptionWithoutError(offer1);
+  EXPECT_EQ(1, session_->remote_description()->candidates(0)->count());
+
+  // The second offer has the same ufrag and pwd but different address.
+  sdp.clear();
+  ModifyIceUfragPwdLines(offer.get(), "0123456789012345",
+                         "abcdefghijklmnopqrstuvwx", &sdp);
+  SessionDescriptionInterface* offer2 =
+      CreateSessionDescription(JsepSessionDescription::kOffer, sdp, NULL);
+  candidate1.set_address(rtc::SocketAddress("1.1.1.1", 6000));
+  JsepIceCandidate ice_candidate2(kMediaContentName0, kMediaContentIndex0,
+                                  candidate1);
+  EXPECT_TRUE(offer2->AddCandidate(&ice_candidate2));
+  SetRemoteDescriptionWithoutError(offer2);
+  EXPECT_EQ(2, session_->remote_description()->candidates(0)->count());
+
+  // The third offer has a different pwd and different address.

[juberti1, 2015/07/31 05:55:21]

this should really be a changed ufrag. Changing the pwd should never happen
without a changed ufrag.

[honghaiz3, 2015/07/31 16:04:34]

Done.

+  sdp.clear();
+  ModifyIceUfragPwdLines(offer.get(), "0123456789012345",
+                         "abcdefghijklmnopqrstuvyz", &sdp);
+  SessionDescriptionInterface* offer3 =
+      CreateSessionDescription(JsepSessionDescription::kOffer, sdp, NULL);
+  candidate1.set_address(rtc::SocketAddress("1.1.1.1", 7000));
+  JsepIceCandidate ice_candidate3(kMediaContentName0, kMediaContentIndex0,
+                                  candidate1);
+  EXPECT_TRUE(offer3->AddCandidate(&ice_candidate3));
+  SetRemoteDescriptionWithoutError(offer3);
+  EXPECT_EQ(1, session_->remote_description()->candidates(0)->count());
+
+  // The fourth offer has no candidate but a different ufrag.
+  sdp.clear();
+  ModifyIceUfragPwdLines(offer.get(), "0123456789012444",
+                         "abcdefghijklmnopqrstuvyz", &sdp);
+  SessionDescriptionInterface* offer4 =
+      CreateSessionDescription(JsepSessionDescription::kOffer, sdp, NULL);
+  SetRemoteDescriptionWithoutError(offer4);
+  EXPECT_EQ(0, session_->remote_description()->candidates(0)->count());
+}
+
 // Test that candidates sent to the "video" transport do not get pushed down to
 // the "audio" transport channel when bundling using TransportProxy.
 TEST_F(WebRtcSessionTest, TestIgnoreCandidatesForUnusedTransportWhenBundling) {
   AddInterface(rtc::SocketAddress(kClientAddrHost1, kClientAddrPort));
 
   InitWithBundlePolicy(PeerConnectionInterface::kBundlePolicyBalanced);
   mediastream_signaling_.SendAudioVideoStream1();
 
   PeerConnectionInterface::RTCOfferAnswerOptions options;
   options.use_rtp_mux = true;
@@ skipping 1291 matching lines @@
     // terminated.  The offer creation may or may not have succeeded, but we
     // must have received a notification which, so the only invalid state
     // is kInit.
     EXPECT_NE(WebRtcSessionCreateSDPObserverForTest::kInit, o->state());
   }
 }
 
 // TODO(bemasc): Add a TestIceStatesBundle with BUNDLE enabled.  That test
 // currently fails because upon disconnection and reconnection OnIceComplete is
 // called more than once without returning to IceGatheringGathering.