Revert "Update includes for webrtc/{base => rtc_base} rename (3/3)"

This reverts commit https://codereview.webrtc.org/2963273002/
where the git cl format breaks include order on Windows.

BUG=webrtc:7634
NOTRY=True
TBR=kwiberg@webrtc.org

Review-Url: https://codereview.webrtc.org/2962303003 .
Cr-Commit-Position: refs/heads/master@{#18857}
diff --git a/webrtc/rtc_base/stringencode.cc b/webrtc/rtc_base/stringencode.cc
index 93470b6..c7d206f 100644
--- a/webrtc/rtc_base/stringencode.cc
+++ b/webrtc/rtc_base/stringencode.cc
@@ -8,13 +8,13 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "webrtc/rtc_base/stringencode.h"
+#include "webrtc/base/stringencode.h"
 
 #include <stdio.h>
 #include <stdlib.h>
 
-#include "webrtc/rtc_base/checks.h"
-#include "webrtc/rtc_base/stringutils.h"
+#include "webrtc/base/checks.h"
+#include "webrtc/base/stringutils.h"
 
 namespace rtc {