Geolocation: extract ContentBrowserClient methods specific to Geolocation into a class

content/public/browser/geolocation_provider.cc

+// Copyright 2016 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 "content/public/browser/geolocation_provider.h"
+
+namespace content {
+
+bool GeolocationProvider::Delegate::UseNetworkLocationProviders() {
+  return true;
+}
+
+AccessTokenStore*
+GeolocationProvider::Delegate::CreateAccessTokenStore() {
+  return nullptr;
+}
+
+LocationProvider*
+GeolocationProvider::Delegate::OverrideSystemLocationProvider() {
+  return nullptr;
+}
+
+}  // namespace content