Cleanup display creation in mus tests.

services/ui/ws/platform_display_default.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 "services/ui/ws/platform_display_default.h"
 
 #include "gpu/ipc/client/gpu_channel_host.h"
 #include "services/ui/display/platform_screen.h"
 #include "services/ui/ws/platform_display_init_params.h"
 #include "services/ui/ws/server_window.h"
@@ skipping 107 matching lines @@
 void PlatformDisplayDefault::SetImeVisibility(bool visible) {
   ui::PlatformImeController* ime = platform_window_->GetPlatformImeController();
   if (ime)
     ime->SetImeVisibility(visible);
 }
 
 gfx::Rect PlatformDisplayDefault::GetBounds() const {
   return metrics_.bounds;
 }
 
-bool PlatformDisplayDefault::IsPrimaryDisplay() const {
-  return display::PlatformScreen::GetInstance()->GetPrimaryDisplayId() ==
-         display_id_;
-}
-
 void PlatformDisplayDefault::OnGpuChannelEstablished(
     scoped_refptr<gpu::GpuChannelHost> channel) {
   frame_generator_->OnGpuChannelEstablished(channel);
 }
 
 bool PlatformDisplayDefault::UpdateViewportMetrics(
     const display::ViewportMetrics& metrics) {
   if (metrics_ == metrics)
     return false;
 
@@ skipping 102 matching lines @@
 }
 
 void PlatformDisplayDefault::OnActivationChanged(bool active) {}
 
 bool PlatformDisplayDefault::IsInHighContrastMode() {
   return delegate_ ? delegate_->IsInHighContrastMode() : false;
 }
 
 }  // namespace ws
 }  // namespace ui