Moves maintaining ShellObservers back to Shell

chrome/browser/ui/ash/chrome_shell_delegate.cc

Index: chrome/browser/ui/ash/chrome_shell_delegate.cc
diff --git a/chrome/browser/ui/ash/chrome_shell_delegate.cc b/chrome/browser/ui/ash/chrome_shell_delegate.cc
index 42db34a1e48b348ec2e98a02a9332ed8c0f1c3bb..34651084b30ff2bddc9703f28c05610d58feafda 100644
--- a/chrome/browser/ui/ash/chrome_shell_delegate.cc
+++ b/chrome/browser/ui/ash/chrome_shell_delegate.cc
@@ -103,10 +103,10 @@ void InitAfterFirstSessionStart() {
 class AccessibilityDelegateImpl : public ash::AccessibilityDelegate {
  public:
   AccessibilityDelegateImpl() {
-    ash::WmShell::Get()->AddShellObserver(AccessibilityManager::Get());
+    ash::Shell::GetInstance()->AddShellObserver(AccessibilityManager::Get());
   }
   ~AccessibilityDelegateImpl() override {
-    ash::WmShell::Get()->RemoveShellObserver(AccessibilityManager::Get());
+    ash::Shell::GetInstance()->RemoveShellObserver(AccessibilityManager::Get());
   }
 
   void ToggleHighContrast() override {