Revert of Moving MediaStreamSignaling logic into PeerConnection.

talk/app/webrtc/webrtcsessiondescriptionfactory.cc

Index: talk/app/webrtc/webrtcsessiondescriptionfactory.cc
diff --git a/talk/app/webrtc/webrtcsessiondescriptionfactory.cc b/talk/app/webrtc/webrtcsessiondescriptionfactory.cc
index d391020cd17cd54bea98322abfb5b1f8a535c2b3..876931539a96e22e5b1a2bfa5803d0fe81c3dd7f 100644
--- a/talk/app/webrtc/webrtcsessiondescriptionfactory.cc
+++ b/talk/app/webrtc/webrtcsessiondescriptionfactory.cc
@@ -31,6 +31,7 @@
 #include "talk/app/webrtc/jsep.h"
 #include "talk/app/webrtc/jsepsessiondescription.h"
 #include "talk/app/webrtc/mediaconstraintsinterface.h"
+#include "talk/app/webrtc/mediastreamsignaling.h"
 #include "talk/app/webrtc/webrtcsession.h"
 #include "webrtc/base/sslidentity.h"
 
@@ -130,13 +131,16 @@
 WebRtcSessionDescriptionFactory::WebRtcSessionDescriptionFactory(
     rtc::Thread* signaling_thread,
     cricket::ChannelManager* channel_manager,
+    MediaStreamSignaling* mediastream_signaling,
     rtc::scoped_ptr<DtlsIdentityStoreInterface> dtls_identity_store,
     const rtc::scoped_refptr<WebRtcIdentityRequestObserver>&
         identity_request_observer,
     WebRtcSession* session,
     const std::string& session_id,
+    cricket::DataChannelType dct,
     bool dtls_enabled)
     : signaling_thread_(signaling_thread),
+      mediastream_signaling_(mediastream_signaling),
       session_desc_factory_(channel_manager, &transport_desc_factory_),
       // RFC 4566 suggested a Network Time Protocol (NTP) format timestamp
       // as the session id and session version. To simplify, it should be fine
@@ -147,6 +151,7 @@
       identity_request_observer_(identity_request_observer),
       session_(session),
       session_id_(session_id),
+      data_channel_type_(dct),
       certificate_request_state_(CERTIFICATE_NOT_NEEDED) {
   session_desc_factory_.set_add_legacy_streams(false);
   // SRTP-SDES is disabled if DTLS is on.
@@ -156,14 +161,18 @@
 WebRtcSessionDescriptionFactory::WebRtcSessionDescriptionFactory(
     rtc::Thread* signaling_thread,
     cricket::ChannelManager* channel_manager,
+    MediaStreamSignaling* mediastream_signaling,
     WebRtcSession* session,
-    const std::string& session_id)
+    const std::string& session_id,
+    cricket::DataChannelType dct)
     : WebRtcSessionDescriptionFactory(signaling_thread,
                                       channel_manager,
+                                      mediastream_signaling,
                                       nullptr,
                                       nullptr,
                                       session,
                                       session_id,
+                                      dct,
                                       false) {
   LOG(LS_VERBOSE) << "DTLS-SRTP disabled.";
 }
@@ -171,17 +180,21 @@
 WebRtcSessionDescriptionFactory::WebRtcSessionDescriptionFactory(
     rtc::Thread* signaling_thread,
     cricket::ChannelManager* channel_manager,
+    MediaStreamSignaling* mediastream_signaling,
     rtc::scoped_ptr<DtlsIdentityStoreInterface> dtls_identity_store,
     WebRtcSession* session,
-    const std::string& session_id)
+    const std::string& session_id,
+    cricket::DataChannelType dct)
     : WebRtcSessionDescriptionFactory(
-          signaling_thread,
-          channel_manager,
-          dtls_identity_store.Pass(),
-          new rtc::RefCountedObject<WebRtcIdentityRequestObserver>(),
-          session,
-          session_id,
-          true) {
+        signaling_thread,
+        channel_manager,
+        mediastream_signaling,
+        dtls_identity_store.Pass(),
+        new rtc::RefCountedObject<WebRtcIdentityRequestObserver>(),
+        session,
+        session_id,
+        dct,
+        true) {
   RTC_DCHECK(dtls_identity_store_);
 
   certificate_request_state_ = CERTIFICATE_WAITING;
@@ -203,16 +216,14 @@
 WebRtcSessionDescriptionFactory::WebRtcSessionDescriptionFactory(
     rtc::Thread* signaling_thread,
     cricket::ChannelManager* channel_manager,
+    MediaStreamSignaling* mediastream_signaling,
     const rtc::scoped_refptr<rtc::RTCCertificate>& certificate,
     WebRtcSession* session,
-    const std::string& session_id)
-    : WebRtcSessionDescriptionFactory(signaling_thread,
-                                      channel_manager,
-                                      nullptr,
-                                      nullptr,
-                                      session,
-                                      session_id,
-                                      true) {
+    const std::string& session_id,
+    cricket::DataChannelType dct)
+    : WebRtcSessionDescriptionFactory(
+        signaling_thread, channel_manager, mediastream_signaling, nullptr,
+        nullptr, session, session_id, dct, true) {
   RTC_DCHECK(certificate);
 
   certificate_request_state_ = CERTIFICATE_WAITING;
@@ -253,8 +264,9 @@
 
 void WebRtcSessionDescriptionFactory::CreateOffer(
     CreateSessionDescriptionObserver* observer,
-    const PeerConnectionInterface::RTCOfferAnswerOptions& options,
-    const cricket::MediaSessionOptions& session_options) {
+    const PeerConnectionInterface::RTCOfferAnswerOptions& options) {
+  cricket::MediaSessionOptions session_options;
+
   std::string error = "CreateOffer";
   if (certificate_request_state_ == CERTIFICATE_FAILED) {
     error += kFailedDueToIdentityFailed;
@@ -263,11 +275,24 @@
     return;
   }
 
+  if (!mediastream_signaling_->GetOptionsForOffer(options,
+                                                  &session_options)) {
+    error += " called with invalid options.";
+    LOG(LS_ERROR) << error;
+    PostCreateSessionDescriptionFailed(observer, error);
+    return;
+  }
+
   if (!ValidStreams(session_options.streams)) {
     error += " called with invalid media streams.";
     LOG(LS_ERROR) << error;
     PostCreateSessionDescriptionFailed(observer, error);
     return;
+  }
+
+  if (data_channel_type_ == cricket::DCT_SCTP &&
+      mediastream_signaling_->HasDataChannels()) {
+    session_options.data_channel_type = cricket::DCT_SCTP;
   }
 
   CreateSessionDescriptionRequest request(
@@ -283,8 +308,7 @@
 
 void WebRtcSessionDescriptionFactory::CreateAnswer(
     CreateSessionDescriptionObserver* observer,
-    const MediaConstraintsInterface* constraints,
-    const cricket::MediaSessionOptions& session_options) {
+    const MediaConstraintsInterface* constraints) {
   std::string error = "CreateAnswer";
   if (certificate_request_state_ == CERTIFICATE_FAILED) {
     error += kFailedDueToIdentityFailed;
@@ -306,15 +330,28 @@
     return;
   }
 
-  if (!ValidStreams(session_options.streams)) {
+  cricket::MediaSessionOptions options;
+  if (!mediastream_signaling_->GetOptionsForAnswer(constraints, &options)) {
+    error += " called with invalid constraints.";
+    LOG(LS_ERROR) << error;
+    PostCreateSessionDescriptionFailed(observer, error);
+    return;
+  }
+  if (!ValidStreams(options.streams)) {
     error += " called with invalid media streams.";
     LOG(LS_ERROR) << error;
     PostCreateSessionDescriptionFailed(observer, error);
     return;
   }
+  // RTP data channel is handled in MediaSessionOptions::AddStream. SCTP streams
+  // are not signaled in the SDP so does not go through that path and must be
+  // handled here.
+  if (data_channel_type_ == cricket::DCT_SCTP) {
+    options.data_channel_type = cricket::DCT_SCTP;
+  }
 
   CreateSessionDescriptionRequest request(
-      CreateSessionDescriptionRequest::kAnswer, observer, session_options);
+      CreateSessionDescriptionRequest::kAnswer, observer, options);
   if (certificate_request_state_ == CERTIFICATE_WAITING) {
     create_session_description_requests_.push(request);
   } else {