Adding CreatePeerConnection method that uses new PC Initialize method.

talk/app/webrtc/peerconnectioninterface.h

Index: talk/app/webrtc/peerconnectioninterface.h
diff --git a/talk/app/webrtc/peerconnectioninterface.h b/talk/app/webrtc/peerconnectioninterface.h
index b7814e583033ac4f741c8d1b245ed14e5c12c143..b254e6c488fdf641e7076fbf84a4ee403e3eaee3 100644
--- a/talk/app/webrtc/peerconnectioninterface.h
+++ b/talk/app/webrtc/peerconnectioninterface.h
@@ -558,13 +558,27 @@ class PeerConnectionFactoryInterface : public rtc::RefCountInterface {
 
   virtual void SetOptions(const Options& options) = 0;
 
-  virtual rtc::scoped_refptr<PeerConnectionInterface>
-      CreatePeerConnection(
-          const PeerConnectionInterface::RTCConfiguration& configuration,
-          const MediaConstraintsInterface* constraints,
-          PortAllocatorFactoryInterface* allocator_factory,
-          rtc::scoped_ptr<DtlsIdentityStoreInterface> dtls_identity_store,
-          PeerConnectionObserver* observer) = 0;
+  // TODO(deadbeef): Remove this overload of CreatePeerConnection once clients
+  // are moved to the new version.
+  virtual rtc::scoped_refptr<PeerConnectionInterface> CreatePeerConnection(
+      const PeerConnectionInterface::RTCConfiguration& configuration,
+      const MediaConstraintsInterface* constraints,
+      PortAllocatorFactoryInterface* allocator_factory,
+      rtc::scoped_ptr<DtlsIdentityStoreInterface> dtls_identity_store,
+      PeerConnectionObserver* observer) {
+    return nullptr;
+  }
+
+  // TODO(deadbeef): Make this pure virtual once it's implemented by all
+  // subclasses.
+  virtual rtc::scoped_refptr<PeerConnectionInterface> CreatePeerConnection(
+      const PeerConnectionInterface::RTCConfiguration& configuration,
+      const MediaConstraintsInterface* constraints,
+      rtc::scoped_ptr<cricket::PortAllocator> allocator,
+      rtc::scoped_ptr<DtlsIdentityStoreInterface> dtls_identity_store,
+      PeerConnectionObserver* observer) {
+    return nullptr;
+  }
 
   // TODO(hbos): Remove below version after clients are updated to above method.
   // In latest W3C WebRTC draft, PC constructor will take RTCConfiguration,