Add more tests for H264 profile level id parsing

webrtc/common_video/h264/profile_level_id.cc

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 121 matching lines @@
 rtc::Optional<std::string> ProfileLevelIdToString(
     const ProfileLevelId& profile_level_id) {
   // Handle special case level == 1b.
   if (profile_level_id.level == kLevel1_b) {
     switch (profile_level_id.profile) {
       case kProfileConstrainedBaseline:
         return rtc::Optional<std::string>("42f00b");
       case kProfileBaseline:
         return rtc::Optional<std::string>("42100b");
       case kProfileMain:
-        return rtc::Optional<std::string>("4D100b");
+        return rtc::Optional<std::string>("4d100b");
       // Level 1b is not allowed for other profiles.
       default:
         return rtc::Optional<std::string>();
     }
   }
 
   const char* profile_idc_iop_string;
   switch (profile_level_id.profile) {
     case kProfileConstrainedBaseline:
       profile_idc_iop_string = "42e0";
       break;
     case kProfileBaseline:
       profile_idc_iop_string = "4200";
       break;
     case kProfileMain:
-      profile_idc_iop_string = "4D00";
+      profile_idc_iop_string = "4d00";
       break;
     case kProfileConstrainedHigh:
       profile_idc_iop_string = "640c";
       break;
     case kProfileHigh:
       profile_idc_iop_string = "6400";
       break;
     // Unrecognized profile.
     default:
       return rtc::Optional<std::string>();
   }
 
   char str[7];
   snprintf(str, 7u, "%s%02x", profile_idc_iop_string, profile_level_id.level);
   return rtc::Optional<std::string>(str);
 }
 
 }  // namespace H264
 }  // namespace webrtc