chromeos: Refactor shelf to create ShelfView earlier in startup

chrome/browser/chromeos/accessibility/accessibility_manager.cc

 // Copyright (c) 2013 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 "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 1494 matching lines @@
     chromevox_panel_->Close();
     chromevox_panel_ = nullptr;
   }
   chromevox_panel_ = new ChromeVoxPanel(
       profile_, session_manager::SessionManager::Get()->IsUserSessionBlocked());
   chromevox_panel_widget_observer_.reset(
       new ChromeVoxPanelWidgetObserver(chromevox_panel_->GetWidget(), this));
 }
 
 void AccessibilityManager::OnChromeVoxPanelClosing() {
-  aura::Window* root_window = chromevox_panel_->GetRootWindow();
-  chromevox_panel_widget_observer_.reset(nullptr);
+  chromevox_panel_->ResetPanelHeight();
+  chromevox_panel_widget_observer_.reset();
   chromevox_panel_ = nullptr;
-
-  ash::WmShelf* shelf =
-      ash::WmShelf::ForWindow(ash::WmWindow::Get(root_window));
-  if (!shelf->IsShelfInitialized())
-    return;
-
-  ash::ShelfLayoutManager* shelf_layout_manager = shelf->shelf_layout_manager();
-  if (shelf_layout_manager)
-    shelf_layout_manager->SetChromeVoxPanelHeight(0);

[James Cook, 2017/05/16 21:32:36]

This code was kind-of copy/pasted so I collapsed the copies.

 }
 
 void AccessibilityManager::OnChromeVoxPanelDestroying() {
   chromevox_panel_widget_observer_.reset(nullptr);
   chromevox_panel_ = nullptr;
 }
 
 void AccessibilityManager::SetKeyboardListenerExtensionId(
     const std::string& id,
     content::BrowserContext* context) {
   keyboard_listener_extension_id_ = id;
 
   extensions::ExtensionRegistry* registry =
       extensions::ExtensionRegistry::Get(context);
   if (!extension_registry_observer_.IsObserving(registry) && !id.empty())
     extension_registry_observer_.Add(registry);
 }
 
 }  // namespace chromeos