[GCM] Reland: Introduce GCMClientFactory to create GCMClient for GCMProfileService

google_apis/gcm/gcm_client.cc

 // Copyright 2013 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 "google_apis/gcm/gcm_client.h"
 
-#include "base/lazy_instance.h"
-#include "google_apis/gcm/gcm_client_impl.h"
-
 namespace gcm {
 
-namespace {
-
-static base::LazyInstance<GCMClientImpl>::Leaky g_gcm_client =
-    LAZY_INSTANCE_INITIALIZER;
-static GCMClient::TestingFactoryFunction g_gcm_client_factory = NULL;
-static GCMClient* g_gcm_client_override = NULL;
-
-}  // namespace
-
 GCMClient::OutgoingMessage::OutgoingMessage()
     : time_to_live(0) {
 }
 
 GCMClient::OutgoingMessage::~OutgoingMessage() {
 }
 
 GCMClient::IncomingMessage::IncomingMessage() {
 }
 
 GCMClient::IncomingMessage::~IncomingMessage() {
 }
 
-// static
-GCMClient* GCMClient::Get() {
-  if (g_gcm_client_override)
-    return g_gcm_client_override;
-  if (g_gcm_client_factory) {
-    g_gcm_client_override = g_gcm_client_factory();
-    return g_gcm_client_override;
-  }
-  return g_gcm_client.Pointer();
+GCMClient::GCMClient() {
 }
 
-// static
-void GCMClient::SetTestingFactory(TestingFactoryFunction factory) {
-  if (g_gcm_client_override) {
-    delete g_gcm_client_override;
-    g_gcm_client_override = NULL;
-  }
-  g_gcm_client_factory = factory;
+GCMClient::~GCMClient() {
 }
 
 }  // namespace gcm