Add option for not adding '.0' to the end of doubles that have no fractional

chrome/test/webdriver/commands/response.cc

Index: chrome/test/webdriver/commands/response.cc
diff --git a/chrome/test/webdriver/commands/response.cc b/chrome/test/webdriver/commands/response.cc
index bef138635627ee1169c4913d9a936e179e09dc04..41ea8d8190e9b8aa30ec6fb7887ee6c5e0c5c35e 100644
--- a/chrome/test/webdriver/commands/response.cc
+++ b/chrome/test/webdriver/commands/response.cc
@@ -71,7 +71,13 @@ const Value* Response::GetDictionary() const {
 
 std::string Response::ToJSON() const {
   std::string json;
-  base::JSONWriter::Write(&data_, false, &json);
+  // The |Value| classes do not support int64 and in rare cases we need to
+  // return one. We do this by using a double and passing in the special
+  // option so that the JSONWriter doesn't add '.0' to the end and confuse
+  // the WebDriver client.
+  base::JSONWriter::WriteWithOptions(
+      &data_, false,
+      base::JSONWriter::OPTIONS_ALLOW_DOUBLES_AS_INTEGERS, &json);
   return json;
 }