Move Mus into chrome's process when running with --mus.

services/ui/display/screen_manager_forwarding.cc

 // Copyright 2017 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 "services/ui/display/screen_manager_forwarding.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "services/service_manager/public/cpp/bind_source_info.h"
@@ skipping 19 matching lines @@
         mode->refresh_rate() == mode_to_find->refresh_rate()) {
       return mode.get();
     }
   }
   NOTREACHED();
   return nullptr;
 }
 
 }  // namespace
 
-ScreenManagerForwarding::ScreenManagerForwarding()
+ScreenManagerForwarding::ScreenManagerForwarding(bool in_process)
     : screen_(base::MakeUnique<display::ScreenBase>()), binding_(this) {
-  Screen::SetScreenInstance(screen_.get());
+  // TODO: We should probably have Mus use Ash's screen and not create a screen
+  // here at all for the in-process case. We'd need to add GetAllDisplays() to
+  // display::Screen to achieve that.
+  // Currently WS still uses this Screen, accessing it via
+  // ScreenManager::GetInstance()->GetScreen() (rather than Screen::GetScreen())
+  if (!in_process)
+    Screen::SetScreenInstance(screen_.get());
 }
 
 ScreenManagerForwarding::~ScreenManagerForwarding() {
   if (native_display_delegate_)
     native_display_delegate_->RemoveObserver(this);
   Screen::SetScreenInstance(nullptr);
 }
 
 void ScreenManagerForwarding::AddInterfaces(
     service_manager::BinderRegistry* registry) {
@@ skipping 158 matching lines @@
   if (status) {
     // Modify display snapshot similar to how ConfigureDisplaysTask would. Ozone
     // DRM needs these to be changed and ConfigureDisplaysTasks can't do it.
     snapshot->set_current_mode(mode);
     snapshot->set_origin(origin);
   }
   callback.Run(status);
 }
 
 }  // namespace display