DesktopAura: Track windows "owned" via the DesktopWindowTreeHost

ui/views/mus/desktop_window_tree_host_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/desktop_window_tree_host_mus.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/cursor_client.h"
@@ skipping 167 matching lines @@
       native_widget_delegate_(native_widget_delegate),
       desktop_native_widget_aura_(desktop_native_widget_aura),
       fullscreen_restore_state_(ui::SHOW_STATE_DEFAULT),
       close_widget_factory_(this) {
   aura::Env::GetInstance()->AddObserver(this);
   MusClient::Get()->AddObserver(this);
   native_widget_delegate_->AsWidget()->AddObserver(this);
   // DesktopNativeWidgetAura registers the association between |content_window_|
   // and Widget, but code may also want to go from the root (window()) to the
   // Widget. This call enables that.
   NativeWidgetAura::RegisterNativeWidgetForWindow(desktop_native_widget_aura,

[tapted, 2017/01/25 11:23:03]

I tried moving this up to DesktopNativeWidgetAura to be shared by all
DesktopWindowTreeHosts in Patchsets 5/6. The code was much simpler, but it
resulted in a very obscure ASAN error in a single test. It looks like the
aura::Window that WebContentsViewAura creates directly is triggering the
destruction of a Widget that it didn't create in a way that causes some weird
lifetime problems. So, there may be a trap lurking here for mus in the future..

[sky, 2017/01/25 16:41:24]

Interesting...

                                                   window());
   // TODO: use display id and bounds if available, likely need to pass in
   // InitParams for that.
 }
 
 DesktopWindowTreeHostMus::~DesktopWindowTreeHostMus() {
   // The cursor-client can be accessed during WindowTreeHostMus tear-down. So
   // the cursor-client needs to be unset on the root-window before
   // |cursor_manager_| is destroyed.
   aura::client::SetCursorClient(window(), nullptr);
@@ skipping 461 matching lines @@
 bool DesktopWindowTreeHostMus::ShouldUpdateWindowTransparency() const {
   // Needed so the window manager can render the client decorations.
   return false;
 }
 
 bool DesktopWindowTreeHostMus::ShouldUseDesktopNativeCursorManager() const {
   // We manage the cursor ourself.
   return false;
 }
 
+std::vector<DesktopWindowTreeHost*>
+DesktopWindowTreeHostMus::GetOwnedTopLevelHosts() const {
+  return std::vector<DesktopWindowTreeHost*>(children_.begin(),
+                                             children_.end());
+}
+
 void DesktopWindowTreeHostMus::OnWindowManagerFrameValuesChanged() {
   NonClientView* non_client_view =
       native_widget_delegate_->AsWidget()->non_client_view();
   if (non_client_view) {
     non_client_view->Layout();
     non_client_view->SchedulePaint();
   }
 
   SendClientAreaToServer();
   SendHitTestMaskToServer();
@@ skipping 50 matching lines @@
     aura::client::FocusClient* focus_client,
     aura::Window* window) {
   if (window == this->window()) {
     desktop_native_widget_aura_->HandleActivationChanged(true);
   } else if (is_active_) {
     desktop_native_widget_aura_->HandleActivationChanged(false);
   }
 }
 
 }  // namespace views