Tie kWebRtcH264WithOpenH264FFmpeg and kEnableWebRtcHWH264Encoding flags on Mac

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 9ea86ae104896e60939423d78bf63a648abf91c8..ca6694955b36dc2dccba9bd451af5cc9276604a8 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -5546,7 +5546,7 @@ Keep your key file in a safe place. You will need it to create new versions of y
           WebRTC H.264 software video encoder/decoder
         </message>
         <message name="IDS_FLAGS_WEBRTC_H264_WITH_OPENH264_FFMPEG_DESCRIPTION" desc="Description of chrome:flags option to enable WebRTC H.264 sw encoder/decoder">
-          When enabled, an H.264 software video encoder/decoder pair is included. (If a hardware decoder is also available it may be used instead of this decoder).
+          When enabled, an H.264 software video encoder/decoder pair is included. If a hardware encoder/decoder is also available it may be used instead of this encoder/decoder.
         </message>
       </if>
       <message name="IDS_FLAGS_WEBVR_NAME" desc="Name of the 'Enable WebVR' flag.">