Moves maintaining root_window_for_new_windows_ to Shell

ash/shell.cc

Index: ash/shell.cc
diff --git a/ash/shell.cc b/ash/shell.cc
index 6e03f8ecc972d36648cb701c5cd542155a18d90c..b430f12e045e359fd78e67bc50ee38020b43f185 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -246,7 +246,8 @@ aura::Window* Shell::GetPrimaryRootWindow() {
 // static
 aura::Window* Shell::GetTargetRootWindow() {

[James Cook, 2017/03/08 03:04:15]

Hrm, though now it's confusing that we have both. Do you think these two methods
will eventually collapse?

[sky, 2017/03/08 17:01:38]

Indeed. I renamed this to GetRootWindowForNewWindows and added
GetWmRootWindowForNewWindows. The later is temporary while WmWindow exists.

   CHECK(WmShell::HasInstance());
-  return WmWindow::GetAuraWindow(WmShell::Get()->GetRootWindowForNewWindows());
+  return WmWindow::GetAuraWindow(
+      Shell::GetInstance()->GetRootWindowForNewWindows());
 }
 
 // static
@@ -376,6 +377,12 @@ void Shell::SetTouchHudProjectionEnabled(bool enabled) {
     observer.OnTouchHudProjectionToggled(enabled);
 }
 
+WmWindow* Shell::GetRootWindowForNewWindows() {
+  if (scoped_root_window_for_new_windows_)
+    return scoped_root_window_for_new_windows_;
+  return root_window_for_new_windows_;
+}
+
 FirstRunHelper* Shell::CreateFirstRunHelper() {
   return new FirstRunHelperImpl;
 }
@@ -680,14 +687,12 @@ void Shell::Init(const ShellInitParams& init_params) {
       new ::wm::FocusController(focus_rules);
   focus_client_.reset(focus_controller);
   activation_client_ = focus_controller;
-  // TODO(sky): Shell should implement ActivationChangeObserver, not WmShell.
-  activation_client_->AddObserver(wm_shell_.get());
+  activation_client_->AddObserver(this);

[James Cook, 2017/03/08 03:04:15]

Where is this observer removed?

[sky, 2017/03/08 17:01:38]

Looking back at the history AFAICT the code never removed itself. I've added the
removal.

 
   screen_position_controller_.reset(new ScreenPositionController);
 
   wm_shell_->CreatePrimaryHost();
-  wm_shell_->set_root_window_for_new_windows(
-      WmWindow::Get(GetPrimaryRootWindow()));
+  root_window_for_new_windows_ = WmWindow::Get(GetPrimaryRootWindow());
 
   if (!is_mash) {
     resolution_notification_controller_.reset(
@@ -959,4 +964,14 @@ ui::EventTargeter* Shell::GetEventTargeter() {
   return nullptr;
 }
 
+void Shell::OnWindowActivated(
+    aura::client::ActivationChangeObserver::ActivationReason reason,
+    aura::Window* gained_active,
+    aura::Window* lost_active) {
+  // TODO(sky): Shell should implement ActivationChangeObserver, not WmShell.

[James Cook, 2017/03/08 03:04:15]

This TODO looks TODONE.

[sky, 2017/03/08 17:01:38]

Done.

+  WmWindow* gained_active_wm = WmWindow::Get(gained_active);
+  if (gained_active_wm)
+    root_window_for_new_windows_ = gained_active_wm->GetRootWindow();
+}
+
 }  // namespace ash