ash: Explicitly teach various components about ShelfLayoutManager.

ash/system/web_notification/ash_popup_alignment_delegate.cc

 // Copyright 2014 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 "ash/system/web_notification/ash_popup_alignment_delegate.h"
 
 #include "ash/display/window_tree_host_manager.h"
 #include "ash/screen_util.h"
 #include "ash/shelf/shelf_constants.h"
 #include "ash/shelf/shelf_layout_manager.h"
@@ skipping 14 matching lines @@
 
 const int kToastMarginX = 3;
 
 // 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 +
 // shadow).
 const int kNoToastMarginBorderAndShadowOffset = 2;
 
 }
 
-AshPopupAlignmentDelegate::AshPopupAlignmentDelegate()
-    : screen_(NULL), root_window_(NULL), shelf_(NULL), system_tray_height_(0) {
+AshPopupAlignmentDelegate::AshPopupAlignmentDelegate(ShelfLayoutManager* shelf)
+    : screen_(NULL), root_window_(NULL), shelf_(shelf), system_tray_height_(0) {
+  shelf_->AddObserver(this);
 }
 
 AshPopupAlignmentDelegate::~AshPopupAlignmentDelegate() {
   if (screen_)
     screen_->RemoveObserver(this);
   Shell::GetInstance()->RemoveShellObserver(this);
   if (shelf_)

[sky, 2016/02/03 00:01:42]

Remove this conditional as shelf_ is always non-null now (otherwise 37 would
crash).

[sadrul, 2016/02/03 02:07:58]

Done. (fixed up the rest of the code to not check for non-null shelf_ too)

     shelf_->RemoveObserver(this);
 }
 
 void AshPopupAlignmentDelegate::StartObserving(gfx::Screen* screen,
                                                const gfx::Display& display) {
   screen_ = screen;
   work_area_ = display.work_area();
   root_window_ = ash::Shell::GetInstance()
                      ->window_tree_host_manager()
                      ->GetRootWindowForDisplayId(display.id());
-  UpdateShelf();
   screen->AddObserver(this);
   Shell::GetInstance()->AddShellObserver(this);
   if (system_tray_height_ > 0)
     UpdateWorkArea();
 }
 
 void AshPopupAlignmentDelegate::SetSystemTrayHeight(int height) {
   system_tray_height_ = height;
 
   // If the shelf is shown during auto-hide state, the distance from the edge
@@ skipping 48 matching lines @@
 
 void AshPopupAlignmentDelegate::RecomputeAlignment(
     const gfx::Display& display) {
   // Nothing needs to be done.
 }
 
 ShelfAlignment AshPopupAlignmentDelegate::GetAlignment() const {
   return shelf_ ? shelf_->GetAlignment() : SHELF_ALIGNMENT_BOTTOM;
 }
 
-void AshPopupAlignmentDelegate::UpdateShelf() {
-  if (shelf_)
-    return;
-
-  shelf_ = ShelfLayoutManager::ForShelf(root_window_);
-  if (shelf_)
-    shelf_->AddObserver(this);
-}
-
 gfx::Display AshPopupAlignmentDelegate::GetCurrentDisplay() const {
   return gfx::Screen::GetScreen()->GetDisplayNearestWindow(
       shelf_->shelf_widget()->GetNativeView());
 }
 
 void AshPopupAlignmentDelegate::UpdateWorkArea() {
   work_area_ = shelf_->user_work_area_bounds();
   DoUpdateIfPossible();
 }
 
 void AshPopupAlignmentDelegate::OnDisplayWorkAreaInsetsChanged() {
-  UpdateShelf();
   UpdateWorkArea();
 }
 
 void AshPopupAlignmentDelegate::WillChangeVisibilityState(
     ShelfVisibilityState new_state) {
   UpdateWorkArea();
 }
 
 void AshPopupAlignmentDelegate::OnAutoHideStateChanged(
     ShelfAutoHideState new_state) {
   UpdateWorkArea();
 }
 
 void AshPopupAlignmentDelegate::OnDisplayAdded(
     const gfx::Display& new_display) {
 }
 
 void AshPopupAlignmentDelegate::OnDisplayRemoved(
     const gfx::Display& old_display) {
 }
 
 void AshPopupAlignmentDelegate::OnDisplayMetricsChanged(
     const gfx::Display& display,
     uint32_t metrics) {
-  UpdateShelf();
   if (shelf_ && GetCurrentDisplay().id() == display.id())
     UpdateWorkArea();
 }
 
 }  // namespace ash