Create //webrtc/api:libjingle_peerconnection_api + refactorings.

webrtc/pc/mediastreamtrack.h

Index: webrtc/pc/mediastreamtrack.h
diff --git a/webrtc/api/mediastreamtrack.h b/webrtc/pc/mediastreamtrack.h
similarity index 93%
copy from webrtc/api/mediastreamtrack.h
copy to webrtc/pc/mediastreamtrack.h
index 9ba042010f78274e047f21e3098ccf7267456af7..0fb2de2ddcb3c88241e9b5841c730907019096bf 100644
--- a/webrtc/api/mediastreamtrack.h
+++ b/webrtc/pc/mediastreamtrack.h
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#ifndef WEBRTC_API_MEDIASTREAMTRACK_H_
-#define WEBRTC_API_MEDIASTREAMTRACK_H_
+#ifndef WEBRTC_PC_MEDIASTREAMTRACK_H_
+#define WEBRTC_PC_MEDIASTREAMTRACK_H_
 
 #include <string>
 
@@ -59,4 +59,4 @@ class MediaStreamTrack : public Notifier<T> {
 
 }  // namespace webrtc
 
-#endif  // WEBRTC_API_MEDIASTREAMTRACK_H_
+#endif  // WEBRTC_PC_MEDIASTREAMTRACK_H_