Use mojo Shelf interfaces for both mash and classic ash.

chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.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 "chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/chrome_browser_main.h"
 #include "chrome/browser/ui/ash/ash_init.h"
 #include "chrome/browser/ui/ash/ash_util.h"
+#include "chrome/browser/ui/ash/launcher/chrome_launcher_controller_mus.h"
 #include "chrome/browser/ui/views/ash/tab_scrubber.h"
 #include "chrome/browser/ui/views/frame/immersive_context_mus.h"
 #include "chrome/browser/ui/views/frame/immersive_handler_factory_mus.h"
 #include "chrome/common/chrome_switches.h"
 #include "ui/aura/env.h"
 #include "ui/keyboard/content/keyboard.h"
 #include "ui/keyboard/keyboard_controller.h"
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/ui/ash/system_tray_client.h"
@@ skipping 21 matching lines @@
   // For OS_CHROMEOS, virtual keyboard needs to be initialized before profile
   // initialized. Otherwise, virtual keyboard extension will not load at login
   // screen.
   keyboard::InitializeKeyboard();
 
   ui::SelectFileDialog::SetFactory(new SelectFileDialogExtensionFactory);
 #endif  // defined(OS_CHROMEOS)
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostProfileInit() {
-  if (chrome::IsRunningInMash())
-    chrome::InitializeMash();
+  if (chrome::IsRunningInMash()) {
+    DCHECK(!ash::Shell::HasInstance());
+    DCHECK(!ChromeLauncherController::instance());
+    chrome_launcher_controller_mus_ =
+        base::MakeUnique<ChromeLauncherControllerMus>();
+    chrome_launcher_controller_mus_->Init();
+  }
 
   if (!ash::Shell::HasInstance())
     return;
 
   // Initialize TabScrubber after the Ash Shell has been initialized.
   TabScrubber::GetInstance();
   // Activate virtual keyboard after profile is initialized. It depends on the
   // default profile.
   ash::Shell::GetPrimaryRootWindowController()->ActivateKeyboard(
       keyboard::KeyboardController::GetInstance());
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostMainMessageLoopRun() {
 #if defined(OS_CHROMEOS)
   system_tray_client_.reset();
 #endif
   chrome::CloseAsh();
 }