chromeos: turn on simplified display management for mash

ash/mus/bridge/shell_port_mash.cc

Index: ash/mus/bridge/shell_port_mash.cc
diff --git a/ash/mus/bridge/shell_port_mash.cc b/ash/mus/bridge/shell_port_mash.cc
index 1ee218f48b7fc6829b43f7302532effa12efd434..58cc319459f11cdbf288b22bf4d8671f822babb9 100644
--- a/ash/mus/bridge/shell_port_mash.cc
+++ b/ash/mus/bridge/shell_port_mash.cc
@@ -169,8 +169,7 @@ void ShellPortMash::Shutdown() {
 
   ShellPort::Shutdown();
 
-  // TODO(sky): Config::MASH should use WindowTreeHostManager too.
-  if (GetAshConfig() == Config::MUS)
+  if (Shell::ShouldEnableSimplifiedDisplayManagement())
     Shell::Get()->window_tree_host_manager()->Shutdown();
   else
     window_manager_->DeleteAllRootWindowControllers();
@@ -181,7 +180,7 @@ Config ShellPortMash::GetAshConfig() const {
 }
 
 aura::Window* ShellPortMash::GetPrimaryRootWindow() {
-  if (GetAshConfig() == Config::MUS)
+  if (Shell::ShouldEnableSimplifiedDisplayManagement())
     return Shell::Get()->window_tree_host_manager()->GetPrimaryRootWindow();
   // NOTE: This is called before the RootWindowController has been created, so
   // it can't call through to RootWindowController to get all windows.
@@ -189,7 +188,7 @@ aura::Window* ShellPortMash::GetPrimaryRootWindow() {
 }
 
 aura::Window* ShellPortMash::GetRootWindowForDisplayId(int64_t display_id) {
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
     return Shell::Get()->window_tree_host_manager()->GetRootWindowForDisplayId(
         display_id);
   }
@@ -201,8 +200,7 @@ aura::Window* ShellPortMash::GetRootWindowForDisplayId(int64_t display_id) {
 
 const display::ManagedDisplayInfo& ShellPortMash::GetDisplayInfo(
     int64_t display_id) const {
-  // TODO(sky): mash should use this too http://crbug.com/718860.
-  if (GetAshConfig() == Config::MUS)
+  if (Shell::ShouldEnableSimplifiedDisplayManagement())
     return Shell::Get()->display_manager()->GetDisplayInfo(display_id);
 
   // TODO(mash): implement http://crbug.com/622480.
@@ -212,8 +210,7 @@ const display::ManagedDisplayInfo& ShellPortMash::GetDisplayInfo(
 }
 
 bool ShellPortMash::IsActiveDisplayId(int64_t display_id) const {
-  // TODO(sky): mash should use this too http://crbug.com/718860.
-  if (GetAshConfig() == Config::MUS)
+  if (Shell::ShouldEnableSimplifiedDisplayManagement())
     return Shell::Get()->display_manager()->IsActiveDisplayId(display_id);
 
   // TODO(mash): implement http://crbug.com/622480.
@@ -222,8 +219,7 @@ bool ShellPortMash::IsActiveDisplayId(int64_t display_id) const {
 }
 
 display::Display ShellPortMash::GetFirstDisplay() const {
-  // TODO(sky): mash should use this too http://crbug.com/718860.
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
     return Shell::Get()
         ->display_manager()
         ->software_mirroring_display_list()[0];
@@ -235,8 +231,7 @@ display::Display ShellPortMash::GetFirstDisplay() const {
 }
 
 bool ShellPortMash::IsInUnifiedMode() const {
-  // TODO(sky): mash should use this too http://crbug.com/718860.
-  if (GetAshConfig() == Config::MUS)
+  if (Shell::ShouldEnableSimplifiedDisplayManagement())
     return Shell::Get()->display_manager()->IsInUnifiedMode();
 
   // TODO(mash): implement http://crbug.com/622480.
@@ -245,8 +240,7 @@ bool ShellPortMash::IsInUnifiedMode() const {
 }
 
 bool ShellPortMash::IsInUnifiedModeIgnoreMirroring() const {
-  // TODO(sky): mash should use this too http://crbug.com/718860.
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
     return Shell::Get()
                ->display_manager()
                ->current_default_multi_display_mode() ==
@@ -260,7 +254,7 @@ bool ShellPortMash::IsInUnifiedModeIgnoreMirroring() const {
 
 void ShellPortMash::SetDisplayWorkAreaInsets(WmWindow* window,
                                              const gfx::Insets& insets) {
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
     Shell::Get()
         ->window_tree_host_manager()
         ->UpdateWorkAreaOfDisplayNearestWindow(window->aura_window(), insets);
@@ -304,7 +298,7 @@ bool ShellPortMash::IsMouseEventsEnabled() {
 }
 
 std::vector<WmWindow*> ShellPortMash::GetAllRootWindows() {
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
     aura::Window::Windows root_windows =
         Shell::Get()->window_tree_host_manager()->GetAllRootWindows();
     std::vector<WmWindow*> wm_windows(root_windows.size());
@@ -381,7 +375,7 @@ ShellPortMash::CreateMaximizeModeEventHandler() {
 
 std::unique_ptr<ScopedDisableInternalMouseAndKeyboard>
 ShellPortMash::CreateScopedDisableInternalMouseAndKeyboard() {
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
 #if defined(USE_OZONE)
     return base::MakeUnique<ScopedDisableInternalMouseAndKeyboardOzone>();
 #else
@@ -433,9 +427,8 @@ SessionStateDelegate* ShellPortMash::GetSessionStateDelegate() {
 }
 
 void ShellPortMash::AddDisplayObserver(WmDisplayObserver* observer) {
-  // TODO(sky): mash should use the same code as mus/classic and
-  // WmDisplayObserver should be removed; http://crbug.com/718860.
-  if (GetAshConfig() == Config::MASH) {
+  // TODO(sky): WmDisplayObserver should be removed; http://crbug.com/718860.
+  if (!Shell::ShouldEnableSimplifiedDisplayManagement()) {
     NOTIMPLEMENTED();
     return;
   }
@@ -447,9 +440,8 @@ void ShellPortMash::AddDisplayObserver(WmDisplayObserver* observer) {
 }
 
 void ShellPortMash::RemoveDisplayObserver(WmDisplayObserver* observer) {
-  // TODO(sky): mash should use the same code as mus/classic and
-  // WmDisplayObserver should be removed; http://crbug.com/718860.
-  if (GetAshConfig() == Config::MASH) {
+  // TODO(sky): WmDisplayObserver should be removed; http://crbug.com/718860.
+  if (!Shell::ShouldEnableSimplifiedDisplayManagement()) {
     NOTIMPLEMENTED();
     return;
   }
@@ -525,8 +517,7 @@ void ShellPortMash::CreatePointerWatcherAdapter() {
 
 std::unique_ptr<AshWindowTreeHost> ShellPortMash::CreateAshWindowTreeHost(
     const AshWindowTreeHostInitParams& init_params) {
-  // TODO(sky): make this work for mash too.
-  if (GetAshConfig() != Config::MUS)
+  if (!Shell::ShouldEnableSimplifiedDisplayManagement())
     return nullptr;
 
   std::unique_ptr<aura::DisplayInitParams> display_params =
@@ -566,17 +557,16 @@ void ShellPortMash::OnCreatedRootWindowContainers(
 }
 
 void ShellPortMash::CreatePrimaryHost() {
-  if (GetAshConfig() == Config::MASH)
+  if (!Shell::ShouldEnableSimplifiedDisplayManagement())
     return;
 
-  DCHECK_EQ(Config::MUS, GetAshConfig());
   Shell::Get()->window_tree_host_manager()->Start();
   AshWindowTreeHostInitParams ash_init_params;
   Shell::Get()->window_tree_host_manager()->CreatePrimaryHost(ash_init_params);
 }
 
 void ShellPortMash::InitHosts(const ShellInitParams& init_params) {
-  if (GetAshConfig() == Config::MUS) {
+  if (Shell::ShouldEnableSimplifiedDisplayManagement()) {
     Shell::Get()->window_tree_host_manager()->InitHosts();
   } else {
     window_manager_->CreatePrimaryRootWindowController(