Update from https://crrev.com/309415

base/json/json_value_converter.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/json/json_value_converter.h"
+
+namespace base {
+namespace internal {
+
+bool BasicValueConverter<int>::Convert(
+    const base::Value& value, int* field) const {
+  return value.GetAsInteger(field);
+}
+
+bool BasicValueConverter<std::string>::Convert(
+    const base::Value& value, std::string* field) const {
+  return value.GetAsString(field);
+}
+
+bool BasicValueConverter<string16>::Convert(
+    const base::Value& value, string16* field) const {
+  return value.GetAsString(field);
+}
+
+bool BasicValueConverter<double>::Convert(
+    const base::Value& value, double* field) const {
+  return value.GetAsDouble(field);
+}
+
+bool BasicValueConverter<bool>::Convert(
+    const base::Value& value, bool* field) const {
+  return value.GetAsBoolean(field);
+}
+
+}  // namespace internal
+}  // namespace base
+