third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/src/google/protobuf/stubs/strutil.cc

Index: third_party/protobuf/src/google/protobuf/stubs/strutil.cc
diff --git a/third_party/protobuf/src/google/protobuf/stubs/strutil.cc b/third_party/protobuf/src/google/protobuf/stubs/strutil.cc
index 7ba92e8f1fa4d95dd77feb4a14abe6aa1326c1b7..4fa8e99f4f25c28622ae82b3c7da1eea60df6ff2 100644
--- a/third_party/protobuf/src/google/protobuf/stubs/strutil.cc
+++ b/third_party/protobuf/src/google/protobuf/stubs/strutil.cc
@@ -93,6 +93,21 @@ void StripString(string* s, const char* remove, char replacewith) {
   }
 }
 
+// ----------------------------------------------------------------------
+// ReplaceCharacters
+//    Replaces any occurrence of the character 'remove' (or the characters
+//    in 'remove') with the character 'replacewith'.
+// ----------------------------------------------------------------------
+void ReplaceCharacters(string *s, const char *remove, char replacewith) {
+  const char *str_start = s->c_str();
+  const char *str = str_start;
+  for (str = strpbrk(str, remove);
+       str != NULL;
+       str = strpbrk(str + 1, remove)) {
+    (*s)[str - str_start] = replacewith;
+  }
+}
+
 void StripWhitespace(string* str) {
   int str_length = str->length();