[mus+ash] Removes WmWindow from ash/shelf and ash/shell

ash/system/web_notification/ash_popup_alignment_delegate.cc

Index: ash/system/web_notification/ash_popup_alignment_delegate.cc
diff --git a/ash/system/web_notification/ash_popup_alignment_delegate.cc b/ash/system/web_notification/ash_popup_alignment_delegate.cc
index ae39d5e38a672db454e8523036510fb844c7f38b..08097b68db2cba771741230b41e128827d39575d 100644
--- a/ash/system/web_notification/ash_popup_alignment_delegate.cc
+++ b/ash/system/web_notification/ash_popup_alignment_delegate.cc
@@ -26,7 +26,7 @@ namespace {
 const int kToastMarginX = 7;
 
 // If there should be no margin for the first item, this value needs to be
-// substracted to flush the message to the shelf (the width of the border +
+// subtracted to flush the message to the shelf (the width of the border +
 // shadow).
 const int kNoToastMarginBorderAndShadowOffset = 2;
 
@@ -116,8 +116,7 @@ void AshPopupAlignmentDelegate::ConfigureWidgetInitParamsForContainer(
   init_params->shadow_type = views::Widget::InitParams::SHADOW_TYPE_DROP;
   init_params->shadow_elevation = ::wm::ShadowElevation::MEDIUM;
   // On ash, popups go in the status container.
-  shelf_->GetWindow()
-      ->GetRootWindowController()
+  RootWindowController::ForWindow(shelf_->GetWindow())
       ->ConfigureWidgetInitParamsForContainer(
           widget, kShellWindowId_StatusContainer, init_params);
 }
@@ -132,7 +131,8 @@ ShelfAlignment AshPopupAlignmentDelegate::GetAlignment() const {
 }
 
 display::Display AshPopupAlignmentDelegate::GetCurrentDisplay() const {
-  return shelf_->GetWindow()->GetDisplayNearestWindow();
+  return display::Screen::GetScreen()->GetDisplayNearestWindow(
+      shelf_->GetWindow());
 }
 
 void AshPopupAlignmentDelegate::UpdateWorkArea() {