Build WebRTC with data channel only.

webrtc/pc/peerconnection_integrationtest.cc

Index: webrtc/pc/peerconnection_integrationtest.cc
diff --git a/webrtc/pc/peerconnection_integrationtest.cc b/webrtc/pc/peerconnection_integrationtest.cc
index 2c19c8d93ebfd1360207b873fd73aeb65f0f6635..973470d350f092036ddb151df055e51d4d4eb879 100644
--- a/webrtc/pc/peerconnection_integrationtest.cc
+++ b/webrtc/pc/peerconnection_integrationtest.cc
@@ -2313,6 +2313,36 @@ TEST_F(PeerConnectionIntegrationTest, EndToEndCallWithSctpDataChannel) {
                  kDefaultTimeout);
 }
 
+// This test sets up a call between two parties with an SCTP data channel only.
+TEST_F(PeerConnectionIntegrationTest, EndToEndCallWithSctpDataChannelOnly) {
+  ASSERT_TRUE(CreatePeerConnectionWrappers());
+  ConnectFakeSignaling();
+  // Expect that data channel created on caller side will show up for callee as
+  // well.
+  caller()->CreateDataChannel();
+  PeerConnectionInterface::RTCOfferAnswerOptions options;
+  options.offer_to_receive_audio = 0;
+  options.offer_to_receive_video = 0;
+  caller()->SetOfferAnswerOptions(options);
+  caller()->CreateAndSetAndSignalOffer();
+  ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
+  // Caller data channel should already exist (it created one). Callee data
+  // channel may not exist yet, since negotiation happens in-band, not in SDP.
+  ASSERT_NE(nullptr, caller()->data_channel());
+  ASSERT_TRUE_WAIT(callee()->data_channel() != nullptr, kDefaultTimeout);
+  EXPECT_TRUE_WAIT(caller()->data_observer()->IsOpen(), kDefaultTimeout);
+  EXPECT_TRUE_WAIT(callee()->data_observer()->IsOpen(), kDefaultTimeout);
+
+  // Ensure data can be sent in both directions.
+  std::string data = "hello world";
+  caller()->data_channel()->Send(DataBuffer(data));
+  EXPECT_EQ_WAIT(data, callee()->data_observer()->last_message(),
+                 kDefaultTimeout);
+  callee()->data_channel()->Send(DataBuffer(data));
+  EXPECT_EQ_WAIT(data, caller()->data_observer()->last_message(),
+                 kDefaultTimeout);
+}
+
 // Ensure that when the callee closes an SCTP data channel, the closing
 // procedure results in the data channel being closed for the caller as well.
 TEST_F(PeerConnectionIntegrationTest, CalleeClosesSctpDataChannel) {