Add the Copresence API.

chrome/browser/extensions/api/copresence/copresence_util.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 "chrome/browser/extensions/api/copresence/copresence_util.h"
+
+#include "chrome/browser/extensions/api/copresence/copresence_api.h"
+#include "components/copresence/public/whispernet_client.h"
+#include "content/public/browser/browser_context.h"
+
+namespace extensions {
+
+CopresenceService* GetCopresenceService(
+    content::BrowserContext* browser_context) {
+  return CopresenceService::GetFactoryInstance()->Get(browser_context);
+}
+
+copresence::CopresenceClient* GetCopresenceClient(
+    content::BrowserContext* browser_context) {
+  CopresenceService* service_ptr = GetCopresenceService(browser_context);
+  return service_ptr ? service_ptr->client() : NULL;
+}
+
+copresence::WhispernetClient* GetWhispernetClient(
+    content::BrowserContext* browser_context) {
+  CopresenceService* service_ptr = GetCopresenceService(browser_context);
+  return service_ptr ? service_ptr->whispernet_client() : NULL;
+}
+
+}  // namespace extensions