ash: Remove ash::Shelf in favor of ash::WmShelf

chrome/browser/chromeos/accessibility/accessibility_manager.cc

Index: chrome/browser/chromeos/accessibility/accessibility_manager.cc
diff --git a/chrome/browser/chromeos/accessibility/accessibility_manager.cc b/chrome/browser/chromeos/accessibility/accessibility_manager.cc
index ad197bb53902b988dfc630d253b3b77181b67e7a..f069aa1f206099714613dcae21d2abb452de4ee4 100644
--- a/chrome/browser/chromeos/accessibility/accessibility_manager.cc
+++ b/chrome/browser/chromeos/accessibility/accessibility_manager.cc
@@ -13,8 +13,8 @@
 #include "ash/aura/wm_window_aura.h"
 #include "ash/autoclick/autoclick_controller.h"
 #include "ash/common/session/session_state_delegate.h"
-#include "ash/common/shelf/shelf.h"
 #include "ash/common/shelf/shelf_layout_manager.h"
+#include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/wm_shell.h"
 #include "ash/high_contrast/high_contrast_controller.h"
 #include "ash/root_window_controller.h"
@@ -1523,9 +1523,9 @@ void AccessibilityManager::OnChromeVoxPanelClosing() {
   chromevox_panel_widget_observer_.reset(nullptr);
   chromevox_panel_ = nullptr;
 
-  ash::Shelf* shelf =
-      ash::Shelf::ForWindow(ash::WmWindowAura::Get(root_window));
-  if (!shelf)
+  ash::WmShelf* shelf =
+      ash::WmShelf::ForWindow(ash::WmWindowAura::Get(root_window));
+  if (!shelf->IsShelfCreated())

[msw, 2016/08/30 22:02:07]

nit: maybe skip this and just let the shelf layout manager check suffice.

[James Cook, 2016/08/30 23:00:57]

I'd prefer to keep this as-is. Otherwise there are additional calls into
SetChromevoxPanelHeight() when you turn Chromevox on and off at the login
screen, since the ShelfLayoutManager exists at that point. While it seems to
work in my manual testing, it's hard for me to be certain that it's safe to
change.

     return;
 
   ash::ShelfLayoutManager* shelf_layout_manager = shelf->shelf_layout_manager();