Adds some TODOs with references to bugs

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 "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/drag_drop_client.h"
 #include "ui/aura/client/focus_client.h"
@@ skipping 113 matching lines @@
 bool DesktopWindowTreeHostMus::IsVisible() const {
   return window()->IsVisible();
 }
 
 void DesktopWindowTreeHostMus::SetSize(const gfx::Size& size) {
   // TODO: handle device scale, http://crbug.com/663524.
   SetBounds(gfx::Rect(window()->bounds().origin(), size));
 }
 
 void DesktopWindowTreeHostMus::StackAbove(aura::Window* window) {
+  // TODO: implement window stacking, http://crbug.com/663617.
   NOTIMPLEMENTED();
 }
 
 void DesktopWindowTreeHostMus::StackAtTop() {
+  // TODO: implement window stacking, http://crbug.com/663617.
   NOTIMPLEMENTED();
 }
 
 void DesktopWindowTreeHostMus::CenterWindow(const gfx::Size& size) {
   NOTIMPLEMENTED();
 }
 
 void DesktopWindowTreeHostMus::GetWindowPlacement(
     gfx::Rect* bounds,
     ui::WindowShowState* show_state) const {
@@ skipping 63 matching lines @@
       aura::client::GetFocusClient(window()), window());
   if (is_active_) {
     window()->Focus();
     if (window()->GetProperty(aura::client::kDrawAttentionKey))
       window()->SetProperty(aura::client::kDrawAttentionKey, false);
   }
 }
 
 void DesktopWindowTreeHostMus::Deactivate() {
   // TODO: Deactivate() means focus next window, that needs to go to mus.
+  // http://crbug.com/663618.
   NOTIMPLEMENTED();
 }
 
 bool DesktopWindowTreeHostMus::IsActive() const {
   return is_active_;
 }
 
 void DesktopWindowTreeHostMus::Maximize() {
   window()->SetProperty(aura::client::kShowStateKey, ui::SHOW_STATE_MAXIMIZED);
 }
@@ skipping 90 matching lines @@
       aura::client::kShowStateKey,
       fullscreen ? ui::SHOW_STATE_FULLSCREEN : fullscreen_restore_state_);
 }
 
 bool DesktopWindowTreeHostMus::IsFullscreen() const {
   return window()->GetProperty(aura::client::kShowStateKey) ==
          ui::SHOW_STATE_FULLSCREEN;
 }
 void DesktopWindowTreeHostMus::SetOpacity(float opacity) {
   // TODO: this likely need to go to server so that non-client decorations get
-  // opacity.
+  // opacity. http://crbug.com/663619.
   window()->layer()->SetOpacity(opacity);
 }
 
 void DesktopWindowTreeHostMus::SetWindowIcons(const gfx::ImageSkia& window_icon,
                                               const gfx::ImageSkia& app_icon) {
   NativeWidgetAura::AssignIconToAuraWindow(window(), window_icon, app_icon);
 }
 
 void DesktopWindowTreeHostMus::InitModalType(ui::ModalType modal_type) {
   window()->SetProperty(aura::client::kModalKey, modal_type);
@@ skipping 59 matching lines @@
   if (window == this->window()) {
     is_active_ = true;
     desktop_native_widget_aura_->HandleActivationChanged(true);
   } else if (is_active_) {
     is_active_ = false;
     desktop_native_widget_aura_->HandleActivationChanged(false);
   }
 }
 
 }  // namespace views