Fix PepperGamepadHostTest.WaitForReply

content/browser/gamepad/gamepad_service.cc

 // Copyright (c) 2012 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/browser/gamepad/gamepad_service.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/singleton.h"
 #include "content/browser/gamepad/gamepad_consumer.h"
 #include "content/browser/gamepad/gamepad_data_fetcher.h"
 #include "content/browser/gamepad/gamepad_provider.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_process_host.h"
 
 namespace content {
 
 namespace {
 GamepadService* g_gamepad_service = 0;
 }
 
 GamepadService::GamepadService()
     : num_active_consumers_(0),
       gesture_callback_pending_(false) {
-  SetInstance();
+  SetInstance(this);
 }
 
 GamepadService::GamepadService(scoped_ptr<GamepadDataFetcher> fetcher)
     : provider_(new GamepadProvider(fetcher.Pass())),
       num_active_consumers_(0),
       gesture_callback_pending_(false) {
-  SetInstance();
+  SetInstance(this);
   thread_checker_.DetachFromThread();
 }
 
 GamepadService::~GamepadService() {
+  SetInstance(NULL);
 }
 
-void GamepadService::SetInstance() {
-  CHECK(!g_gamepad_service);
-  g_gamepad_service = this;
+void GamepadService::SetInstance(GamepadService* instance) {
+  // Unit tests can create multiple instances but only one should exist at any
+  // given time so g_gamepad_service should only go from NULL to non-NULL and
+  // vica versa.
+  CHECK(!!instance != !!g_gamepad_service);
+  g_gamepad_service = instance;
 }
 
 GamepadService* GamepadService::GetInstance() {
   if (!g_gamepad_service)
     g_gamepad_service = new GamepadService;
   return g_gamepad_service;
 }
 
 void GamepadService::ConsumerBecameActive(GamepadConsumer* consumer) {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ skipping 95 matching lines @@
       for (unsigned i = 0; i < blink::WebGamepads::itemsLengthCap; ++i) {
         const blink::WebGamepad& pad = gamepads.items[i];
         if (pad.connected)
           info.consumer->OnGamepadConnected(i, pad);
       }
     }
   }
 }
 
 }  // namespace content