Add abstract interfaces for the transport layer.

remoting/remoting.gyp

Index: remoting/remoting.gyp
diff --git a/remoting/remoting.gyp b/remoting/remoting.gyp
index 996edabc76c9b2c7992d01d7c6a4f62fe8a2e825..741c23734f35f3cb66fabae42b9fcdc782afc60d 100644
--- a/remoting/remoting.gyp
+++ b/remoting/remoting.gyp
@@ -797,13 +797,12 @@
         'protocol/message_reader.h',
         'protocol/negotiating_authenticator.cc',
         'protocol/negotiating_authenticator.h',
-        'protocol/pepper_channel.h',
         'protocol/pepper_session.cc',
         'protocol/pepper_session.h',
         'protocol/pepper_session_manager.cc',
         'protocol/pepper_session_manager.h',
-        'protocol/pepper_stream_channel.cc',
-        'protocol/pepper_stream_channel.h',
+        'protocol/pepper_transport_factory.cc',
+        'protocol/pepper_transport_factory.h',
         'protocol/pepper_transport_socket_adapter.cc',
         'protocol/pepper_transport_socket_adapter.h',
         'protocol/protobuf_video_reader.cc',
@@ -830,6 +829,7 @@
         'protocol/socket_reader_base.h',
         'protocol/ssl_hmac_channel_authenticator.cc',
         'protocol/ssl_hmac_channel_authenticator.h',
+        'protocol/transport.h',
         'protocol/transport_config.cc',
         'protocol/transport_config.h',
         'protocol/util.cc',