Adds option for JSON reader to allow invalid utf characters

base/json/json_parser.h

Index: base/json/json_parser.h
diff --git a/base/json/json_parser.h b/base/json/json_parser.h
index 11a51115de4e4b8c8869a9e1dc02e826b888c606..1cebb8da3ed7b91f4cb2ad2fb5b0b99a77cc31cc 100644
--- a/base/json/json_parser.h
+++ b/base/json/json_parser.h
@@ -257,10 +257,14 @@ class BASE_EXPORT JSONParser {
   FRIEND_TEST_ALL_PREFIXES(JSONParserTest, ConsumeLiterals);
   FRIEND_TEST_ALL_PREFIXES(JSONParserTest, ConsumeNumbers);
   FRIEND_TEST_ALL_PREFIXES(JSONParserTest, ErrorMessages);
+  FRIEND_TEST_ALL_PREFIXES(JSONParserTest, ReplaceInvalidCharacters);
 
   DISALLOW_COPY_AND_ASSIGN(JSONParser);
 };
 
+// Used when decoding and an invalid utf-8 sequence is encountered.
+BASE_EXPORT extern const char kUnicodeReplacementString[];
+
 }  // namespace internal
 }  // namespace base