Address denicija's comments for AppRTCMobile video codec setting.

Comments in review: https://codereview.webrtc.org/2735303004/

BUG=webrtc:7316

Review-Url: https://codereview.webrtc.org/2807533004
Cr-Commit-Position: refs/heads/master@{#17650}
diff --git a/webrtc/examples/objc/AppRTCMobile/ARDSettingsModel.h b/webrtc/examples/objc/AppRTCMobile/ARDSettingsModel.h
index 1787bb2..0f07389 100644
--- a/webrtc/examples/objc/AppRTCMobile/ARDSettingsModel.h
+++ b/webrtc/examples/objc/AppRTCMobile/ARDSettingsModel.h
@@ -53,7 +53,7 @@
 - (NSArray<NSString *> *)availableVideoCodecs;
 
 /**
- * Returns current video codec setting from store if present.
+ * Returns current video codec setting from store if present or default (H264) otherwise.
  */
 - (NSString *)currentVideoCodecSettingFromStore;