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

base/json/json_writer_unittest.cc

Index: base/json/json_writer_unittest.cc
diff --git a/base/json/json_writer_unittest.cc b/base/json/json_writer_unittest.cc
index 5d44c020efa5b59ce405dce26e98e484d60e18fc..fea0c44b787248dd2067cab408d0bdb32cdba69e 100644
--- a/base/json/json_writer_unittest.cc
+++ b/base/json/json_writer_unittest.cc
@@ -119,6 +119,13 @@ TEST(JSONWriterTest, Writing) {
                                JSONWriter::OPTIONS_OMIT_BINARY_VALUES,
                                &output_js);
   ASSERT_EQ("{\"a\":5,\"c\":2}", output_js);
+
+  // Test allowing a double with no fractional part to be written as an integer.
+  FundamentalValue double_value(1e10);
+  JSONWriter::WriteWithOptions(&double_value, false,
+                               JSONWriter::OPTIONS_ALLOW_DOUBLES_AS_INTEGERS,
+                               &output_js);
+  ASSERT_EQ("10000000000", output_js);
 }
 
 }  // namespace base