Convert JsonWriter::Write to taking a const ref for the in-param

base/values.cc

Index: base/values.cc
diff --git a/base/values.cc b/base/values.cc
index 4093eba67aaf39be6ef8f648e49dfebacce1c39c..ebd7157d3c9cc352511f2b7c54521ad79b140fe2 100644
--- a/base/values.cc
+++ b/base/values.cc
@@ -1168,9 +1168,7 @@ ValueDeserializer::~ValueDeserializer() {
 
 std::ostream& operator<<(std::ostream& out, const Value& value) {
   std::string json;
-  JSONWriter::WriteWithOptions(&value,
-                               JSONWriter::OPTIONS_PRETTY_PRINT,
-                               &json);
+  JSONWriter::WriteWithOptions(value, JSONWriter::OPTIONS_PRETTY_PRINT, &json);
   return out << json;
 }