Adds option for JSON reader to allow invalid utf characters

base/json/json_reader.h

Index: base/json/json_reader.h
diff --git a/base/json/json_reader.h b/base/json/json_reader.h
index a954821a288d690648457ae4c250a2a45ba0a4b1..a39b37adeb1cbd516ed9e598277ad4dc515cffd9 100644
--- a/base/json/json_reader.h
+++ b/base/json/json_reader.h
@@ -55,6 +55,11 @@ enum JSONParserOptions {
   // if the child is Remove()d from root, it would result in use-after-free
   // unless it is DeepCopy()ed or this option is used.
   JSON_DETACHABLE_CHILDREN = 1 << 1,
+
+  // If set the parser replaces invalid characters with the Unicode replacement
+  // character (U+FFFD). If not set, invalid characters trigger a hard error and
+  // parsing fails.
+  JSON_REPLACE_INVALID_CHARACTERS = 1 << 2,
 };
 
 class BASE_EXPORT JSONReader {