Revert of Modified PeerConnection and WebRtcSession for end-to-end QuicDataChannel usage.

webrtc/api/test/peerconnectiontestwrapper.cc

Index: webrtc/api/test/peerconnectiontestwrapper.cc
diff --git a/webrtc/api/test/peerconnectiontestwrapper.cc b/webrtc/api/test/peerconnectiontestwrapper.cc
index b1eb58677d310e47461d5fd833fe2a1f436952c1..450a9085207d621ff165189ac6884d916f8632e0 100644
--- a/webrtc/api/test/peerconnectiontestwrapper.cc
+++ b/webrtc/api/test/peerconnectiontestwrapper.cc
@@ -58,8 +58,7 @@
 PeerConnectionTestWrapper::~PeerConnectionTestWrapper() {}
 
 bool PeerConnectionTestWrapper::CreatePc(
-    const MediaConstraintsInterface* constraints,
-    const webrtc::PeerConnectionInterface::RTCConfiguration& config) {
+  const MediaConstraintsInterface* constraints) {
   std::unique_ptr<cricket::PortAllocator> port_allocator(
       new cricket::FakePortAllocator(network_thread_, nullptr));
 
@@ -75,6 +74,11 @@
     return false;
   }
 
+  // CreatePeerConnection with RTCConfiguration.
+  webrtc::PeerConnectionInterface::RTCConfiguration config;
+  webrtc::PeerConnectionInterface::IceServer ice_server;
+  ice_server.uri = "stun:stun.l.google.com:19302";
+  config.servers.push_back(ice_server);
   std::unique_ptr<rtc::RTCCertificateGeneratorInterface> cert_generator(
       rtc::SSLStreamAdapter::HaveDtlsSrtp() ? new FakeRTCCertificateGenerator()
                                             : nullptr);