mus: Initialize WindowManagerConnection in chrome instead of in content.

chrome/browser/ui/views/chrome_browser_main_extra_parts_views.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/chrome_browser_main_extra_parts_views.h"
 
 #include "chrome/browser/ui/views/chrome_constrained_window_views_client.h"
 #include "chrome/browser/ui/views/chrome_views_delegate.h"
 #include "components/constrained_window/constrained_window_views.h"
 
 #if defined(USE_AURA)
 #include "ui/display/screen.h"
 #include "ui/views/widget/desktop_aura/desktop_screen.h"
 #include "ui/wm/core/wm_state.h"
 #endif
 
+#if defined(USE_AURA) && defined(MOJO_SHELL_CLIENT)
+#include "content/public/common/mojo_shell_connection.h"
+#include "ui/views/mus/window_manager_connection.h"
+#endif
+
 ChromeBrowserMainExtraPartsViews::ChromeBrowserMainExtraPartsViews() {
 }
 
 ChromeBrowserMainExtraPartsViews::~ChromeBrowserMainExtraPartsViews() {
   constrained_window::SetConstrainedWindowViewsClient(nullptr);
 }
 
 void ChromeBrowserMainExtraPartsViews::ToolkitInitialized() {
   // The delegate needs to be set before any UI is created so that windows
   // display the correct icon.
   if (!views::ViewsDelegate::GetInstance())
     views_delegate_.reset(new ChromeViewsDelegate);
 
   SetConstrainedWindowViewsClient(CreateChromeConstrainedWindowViewsClient());
 
 #if defined(USE_AURA)
   wm_state_.reset(new wm::WMState);
 #endif
 }
 
 void ChromeBrowserMainExtraPartsViews::PreCreateThreads() {
 #if defined(USE_AURA) && !defined(OS_CHROMEOS)
   display::Screen::SetScreenInstance(views::CreateDesktopScreen());
 #endif
 }
+
+void ChromeBrowserMainExtraPartsViews::PreProfileInit() {
+#if defined(USE_AURA) && defined(MOJO_SHELL_CLIENT)
+  content::MojoShellConnection* mojo_shell_connection =
+      content::MojoShellConnection::Get();
+  if (mojo_shell_connection && mojo_shell_connection->UsingExternalShell()) {
+    views::WindowManagerConnection::Create(
+        mojo_shell_connection->GetConnector(),
+        mojo_shell_connection->GetIdentity());
+  }
+#endif
+}