Create //webrtc/api:libjingle_peerconnection_api + refactorings.

webrtc/pc/datachannel.cc

Index: webrtc/pc/datachannel.cc
diff --git a/webrtc/api/datachannel.cc b/webrtc/pc/datachannel.cc
similarity index 99%
rename from webrtc/api/datachannel.cc
rename to webrtc/pc/datachannel.cc
index c0bc3dc42b3e63c341d8bca7107dee0fefb347bb..5606a64c6e2b244b9d16954cdf0c6b4e2038c70a 100644
--- a/webrtc/api/datachannel.cc
+++ b/webrtc/pc/datachannel.cc
@@ -8,16 +8,16 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "webrtc/api/datachannel.h"
+#include "webrtc/pc/datachannel.h"
 
 #include <memory>
 #include <string>
 
-#include "webrtc/api/sctputils.h"
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/refcount.h"
 #include "webrtc/media/sctp/sctptransportinternal.h"
+#include "webrtc/pc/sctputils.h"
 
 namespace webrtc {