Revert of chromeos: Makes mushrome use simplified display management

ash/mus/ash_window_tree_host_mus.cc

Index: ash/mus/ash_window_tree_host_mus.cc
diff --git a/ash/mus/ash_window_tree_host_mus.cc b/ash/mus/ash_window_tree_host_mus.cc
deleted file mode 100644
index 52cb894ff83f132650fd420151375c2b34959af9..0000000000000000000000000000000000000000
--- a/ash/mus/ash_window_tree_host_mus.cc
+++ /dev/null
@@ -1,87 +0,0 @@
-// 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 "ash/mus/ash_window_tree_host_mus.h"
-
-#include "ash/host/root_window_transformer.h"
-#include "ash/host/transformer_helper.h"
-#include "base/memory/ptr_util.h"
-#include "ui/aura/mus/window_tree_host_mus_init_params.h"
-#include "ui/aura/window.h"
-#include "ui/events/null_event_targeter.h"
-
-namespace ash {
-
-AshWindowTreeHostMus::AshWindowTreeHostMus(
-    aura::WindowTreeHostMusInitParams init_params)
-    : aura::WindowTreeHostMus(std::move(init_params)),
-      transformer_helper_(base::MakeUnique<TransformerHelper>(this)) {
-  transformer_helper_->Init();
-}
-
-AshWindowTreeHostMus::~AshWindowTreeHostMus() {}
-
-void AshWindowTreeHostMus::ToggleFullScreen() {
-  NOTIMPLEMENTED();
-}
-
-bool AshWindowTreeHostMus::ConfineCursorToRootWindow() {
-  // TODO: when implementing see implementation in AshWindowTreeHostPlatform
-  // for how it uses |transformer_helper_|.
-  NOTIMPLEMENTED();
-  return true;
-}
-
-void AshWindowTreeHostMus::UnConfineCursor() {
-  NOTIMPLEMENTED();
-}
-
-void AshWindowTreeHostMus::SetRootWindowTransformer(
-    std::unique_ptr<RootWindowTransformer> transformer) {
-  transformer_helper_->SetRootWindowTransformer(std::move(transformer));
-  ConfineCursorToRootWindow();
-}
-
-gfx::Insets AshWindowTreeHostMus::GetHostInsets() const {
-  return transformer_helper_->GetHostInsets();
-}
-
-aura::WindowTreeHost* AshWindowTreeHostMus::AsWindowTreeHost() {
-  return this;
-}
-
-void AshWindowTreeHostMus::PrepareForShutdown() {
-  // WindowEventDispatcher may have pending events that need to be processed.
-  // At the time this function is called the WindowTreeHost and Window are in
-  // a semi-shutdown state. Reset the targeter so that the current targeter
-  // doesn't attempt to process events while in this state, which would likely
-  // crash.
-  std::unique_ptr<ui::NullEventTargeter> null_event_targeter =
-      base::MakeUnique<ui::NullEventTargeter>();
-  window()->SetEventTargeter(std::move(null_event_targeter));
-}
-
-void AshWindowTreeHostMus::RegisterMirroringHost(
-    AshWindowTreeHost* mirroring_ash_host) {
-  NOTIMPLEMENTED();
-}
-
-void AshWindowTreeHostMus::SetRootTransform(const gfx::Transform& transform) {
-  transformer_helper_->SetTransform(transform);
-}
-
-gfx::Transform AshWindowTreeHostMus::GetRootTransform() const {
-  return transformer_helper_->GetTransform();
-}
-
-gfx::Transform AshWindowTreeHostMus::GetInverseRootTransform() const {
-  return transformer_helper_->GetInverseTransform();
-}
-
-void AshWindowTreeHostMus::UpdateRootWindowSizeInPixels(
-    const gfx::Size& host_size_in_pixels) {
-  transformer_helper_->UpdateWindowSize(host_size_in_pixels);
-}
-
-}  // namespace ash