Fix: Adding list of supported codecs for MP4 containers

base/strings/string_util.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/strings/string_util.h"
 
 #include <ctype.h>
 #include <errno.h>
 #include <math.h>
 #include <stdarg.h>
@@ skipping 326 matching lines @@
 }
 
 bool IsStringASCII(const base::StringPiece& str) {
   return DoIsStringASCII(str);
 }
 
 bool IsStringASCII(const base::string16& str) {
   return DoIsStringASCII(str);
 }
 
+bool IsUpperCaseHexNumber(const std::string& number) {
+  if (!number.length())
+    return false;
+
+  for (size_t i = 0; i < number.length(); ++i) {
+    if (!IsUpperCaseHexDigit(number.at(i)))
+      return false;
+  }
+
+  return true;
+}
+
 bool IsStringUTF8(const std::string& str) {
   const char *src = str.data();
   int32 src_len = static_cast<int32>(str.length());
   int32 char_index = 0;
 
   while (char_index < src_len) {
     int32 code_point;
     CBU8_NEXT(src, char_index, src_len, code_point);
     if (!base::IsValidCharacter(code_point))
       return false;
@@ skipping 530 matching lines @@
 }
 
 }  // namespace
 
 size_t base::strlcpy(char* dst, const char* src, size_t dst_size) {
   return lcpyT<char>(dst, src, dst_size);
 }
 size_t base::wcslcpy(wchar_t* dst, const wchar_t* src, size_t dst_size) {
   return lcpyT<wchar_t>(dst, src, dst_size);
 }