Add enable-app-launcher-shim to chrome://flags.

chrome/browser/ui/app_list/app_list_service_mac.mm

 // 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 "apps/app_shim/app_shim_handler_mac.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_nsobject.h"
@@ skipping 122 matching lines @@
 
   // TODO(tapted): Create a dock icon using chrome/browser/mac/dock.h .
   web_app::CreateShortcuts(shortcut_info,
                            ShellIntegration::ShortcutLocations());
 }
 
 // Check that there is an app list shim. If enabling and there is not, make one.
 // If disabling with --enable-app-list-shim=0, and there is one, delete it.
 void CheckAppListShimOnFileThread(const base::FilePath& profile_path) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::FILE));
-  const bool enable = CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
-      switches::kEnableAppListShim).c_str()[0] != '0';
+  const bool enable =
+      CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableAppListShim);
   base::FilePath install_path = web_app::GetAppInstallPath(
       GetAppListShortcutInfo(profile_path));
   if (enable == file_util::PathExists(install_path))
     return;
 
   if (enable) {
     content::BrowserThread::PostTask(
         content::BrowserThread::UI, FROM_HERE,
         base::Bind(&CreateAppListShim, profile_path));
     return;
@@ skipping 52 matching lines @@
   [[window_controller_ appListViewController] setDelegate:delegate.Pass()];
 }
 
 void AppListServiceMac::Init(Profile* initial_profile) {
   // On Mac, Init() is called multiple times for a process: any time there is no
   // browser window open and a new window is opened, and during process startup
   // to handle the silent launch case (e.g. for app shims). In the startup case,
   // a profile has not yet been determined so |initial_profile| will be NULL.
   if (initial_profile) {
     static bool checked_shim = false;
-    if (!checked_shim && CommandLine::ForCurrentProcess()->HasSwitch(
-            switches::kEnableAppListShim)) {
+    if (!checked_shim) {
       checked_shim = true;
       content::BrowserThread::PostTask(
           content::BrowserThread::FILE, FROM_HERE,
           base::Bind(&CheckAppListShimOnFileThread,
                      initial_profile->GetPath()));
     }
   }
 
   static bool init_called = false;
   if (init_called)
@@ skipping 136 matching lines @@
 
 // static
 AppListService* AppListService::Get() {
   return AppListServiceMac::GetInstance();
 }
 
 // static
 void AppListService::InitAll(Profile* initial_profile) {
   Get()->Init(initial_profile);
 }