Enable cpplint for more webrtc subfolders and fix all uncovered cpplint errors.

webrtc/common_video/libyuv/include/webrtc_libyuv.h

Index: webrtc/common_video/libyuv/include/webrtc_libyuv.h
diff --git a/webrtc/common_video/libyuv/include/webrtc_libyuv.h b/webrtc/common_video/libyuv/include/webrtc_libyuv.h
index baf8c171adb9f15544652e5914f7ffc350648121..d66736fb248ea958de646c559ffd55c75d4f3fda 100644
--- a/webrtc/common_video/libyuv/include/webrtc_libyuv.h
+++ b/webrtc/common_video/libyuv/include/webrtc_libyuv.h
@@ -152,6 +152,7 @@ int ConvertNV12ToRGB565(const uint8_t* src_frame,
 double I420PSNR(const VideoFrame* ref_frame, const VideoFrame* test_frame);
 // Compute SSIM for an I420 frame (all planes).
 double I420SSIM(const VideoFrame* ref_frame, const VideoFrame* test_frame);
-}
+
+}  // namespace webrtc
 
 #endif  // WEBRTC_COMMON_VIDEO_LIBYUV_INCLUDE_WEBRTC_LIBYUV_H_