[Mac] Make --apps-keep-chrome-alive on by default.

chrome/browser/ui/cocoa/apps/quit_with_apps_controller_mac.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/ui/cocoa/apps/quit_with_apps_controller_mac.h"
 
 #include "apps/app_window.h"
 #include "apps/app_window_registry.h"
 #include "apps/ui/native_app_window.h"
 #include "base/command_line.h"
@@ skipping 86 matching lines @@
   return NULL;
 }
 
 std::string QuitWithAppsController::id() const {
   return kQuitWithAppsNotificationID;
 }
 
 bool QuitWithAppsController::ShouldQuit() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
-  if (!CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kAppsKeepChromeAlive)) {
-    g_browser_process->local_state()->ClearPref(
-        prefs::kNotifyWhenAppsKeepChromeAlive);
+  // Quit immediately if this is a test.
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kTestType) &&
+      !CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kAppsKeepChromeAliveInTests)) {
     return true;
   }
 
   // Quit immediately if there are no windows or the confirmation has been
   // suppressed.
   if (!apps::AppWindowRegistry::IsAppWindowRegisteredInAnyProfile(0))
     return true;
 
   // If there are browser windows, and this notification has been suppressed for
   // this session or permanently, then just return false to prevent Chrome from
@@ skipping 18 matching lines @@
 
   // Always return false, the notification UI can be used to quit all apps which
   // will cause Chrome to quit.
   return false;
 }
 
 // static
 void QuitWithAppsController::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterBooleanPref(prefs::kNotifyWhenAppsKeepChromeAlive, true);
 }