Simple CL to fix lint errors in webrtc/modules/remote_bitrate_estimator. Added the lint check for the folder to the presubmit script.

BUG=webrtc:5310

Review URL: https://codereview.webrtc.org/1520513003

Cr-Commit-Position: refs/heads/master@{#11021}

PRESUBMIT.py

diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index cd356ca..9db9d82 100755
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -20,6 +20,7 @@
   'webrtc/call',
   'webrtc/common_video',
   'webrtc/examples',
+  'webrtc/modules/remote_bitrate_estimator',
   'webrtc/modules/video_processing',
   'webrtc/sound',
   'webrtc/tools',