Fixing WebRTC after moving from src/webrtc to src/

In https://webrtc-review.googlesource.com/c/src/+/1560 we moved WebRTC
from src/webrtc to src/ (in order to preserve an healthy git history).
This CL takes care of fixing header guards, #include paths, etc...

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org


Bug: chromium:611808
Change-Id: Iea91618212bee0af16aa3f05071eab8f93706578
Reviewed-on: https://webrtc-review.googlesource.com/1561
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19846}
diff --git a/modules/bitrate_controller/include/bitrate_controller.h b/modules/bitrate_controller/include/bitrate_controller.h
index f479e52..52347a3 100644
--- a/modules/bitrate_controller/include/bitrate_controller.h
+++ b/modules/bitrate_controller/include/bitrate_controller.h
@@ -12,15 +12,15 @@
  *  and push the result to the encoders via BitrateObserver(s).
  */
 
-#ifndef WEBRTC_MODULES_BITRATE_CONTROLLER_INCLUDE_BITRATE_CONTROLLER_H_
-#define WEBRTC_MODULES_BITRATE_CONTROLLER_INCLUDE_BITRATE_CONTROLLER_H_
+#ifndef MODULES_BITRATE_CONTROLLER_INCLUDE_BITRATE_CONTROLLER_H_
+#define MODULES_BITRATE_CONTROLLER_INCLUDE_BITRATE_CONTROLLER_H_
 
 #include <map>
 
-#include "webrtc/modules/congestion_controller/delay_based_bwe.h"
-#include "webrtc/modules/include/module.h"
-#include "webrtc/modules/pacing/paced_sender.h"
-#include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
+#include "modules/congestion_controller/delay_based_bwe.h"
+#include "modules/include/module.h"
+#include "modules/pacing/paced_sender.h"
+#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
 
 namespace webrtc {
 
@@ -97,4 +97,4 @@
                                     int64_t* rtt) = 0;
 };
 }  // namespace webrtc
-#endif  // WEBRTC_MODULES_BITRATE_CONTROLLER_INCLUDE_BITRATE_CONTROLLER_H_
+#endif  // MODULES_BITRATE_CONTROLLER_INCLUDE_BITRATE_CONTROLLER_H_