Reinstate wait-for-Initialize when Chrome is run in Mash

ui/views/mus/screen_mus.cc

 // Copyright 2016 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 "ui/views/mus/screen_mus.h"
 
 #include "mojo/converters/geometry/geometry_type_converters.h"
 #include "mojo/shell/public/cpp/connection.h"
 #include "mojo/shell/public/cpp/connector.h"
 #include "ui/gfx/display_finder.h"
@@ skipping 65 matching lines @@
 
 void ScreenMus::Init(mojo::Connector* connector) {
   gfx::Screen::SetScreenInstance(this);
 
   connector->ConnectToInterface("mojo:mus", &display_manager_);
 
   display_manager_->AddObserver(
       display_manager_observer_binding_.CreateInterfacePtrAndBind());
 
   // We need the set of displays before we can continue. Wait for it.
-  wait_for_displays_loop_.reset(new base::RunLoop);
-  wait_for_displays_loop_->Run();
+  //
+  // TODO(rockot): Do something better here. This should not have to block tasks
+  // from running on the calling thread. http://crbug.com/594852.
+  display_manager_observer_binding_.WaitForIncomingMethodCall();
 
   // The WaitForIncomingMethodCall() should have supplied the set of Displays.
   DCHECK(displays_.size());
 }
 
 int ScreenMus::FindDisplayIndexById(int64_t id) const {
   for (size_t i = 0; i < displays_.size(); ++i) {
     if (displays_[i].id() == id)
       return static_cast<int>(i);
   }
@@ skipping 99 matching lines @@
   displays_ = displays.To<std::vector<gfx::Display>>();
   for (size_t i = 0; i < displays.size(); ++i) {
     if (displays[i]->is_primary) {
       primary_display_index_ = static_cast<int>(i);
       // TODO(sky): Make WindowManagerFrameValues per display.
       WindowManagerFrameValues frame_values =
           displays[i]->frame_decoration_values.To<WindowManagerFrameValues>();
       WindowManagerFrameValues::SetInstance(frame_values);
     }
   }
-
-  DCHECK(wait_for_displays_loop_);
-  wait_for_displays_loop_->Quit();
 }
 
 void ScreenMus::OnDisplaysChanged(
     mojo::Array<mus::mojom::DisplayPtr> transport_displays) {
   for (size_t i = 0; i < transport_displays.size(); ++i) {
     const bool is_primary = transport_displays[i]->is_primary;
     ProcessDisplayChanged(transport_displays[i].To<gfx::Display>(), is_primary);
     if (is_primary) {
       WindowManagerFrameValues frame_values =
           transport_displays[i]
               ->frame_decoration_values.To<WindowManagerFrameValues>();
       WindowManagerFrameValues::SetInstance(frame_values);
       delegate_->OnWindowManagerFrameValuesChanged();
     }
   }
 }
 
 void ScreenMus::OnDisplayRemoved(int64_t id) {
   const int index = FindDisplayIndexById(id);
   DCHECK_NE(-1, index);
   // Another display must become primary before the existing primary is
   // removed.
   DCHECK_NE(index, primary_display_index_);
   const gfx::Display display = displays_[index];
   FOR_EACH_OBSERVER(gfx::DisplayObserver, observers_,
                     OnDisplayRemoved(display));
 }
 
 }  // namespace views