Move AccessibilityDelegate ownership to ash::WmShell

ash/accelerators/spoken_feedback_toggler.cc

Index: ash/accelerators/spoken_feedback_toggler.cc
diff --git a/ash/accelerators/spoken_feedback_toggler.cc b/ash/accelerators/spoken_feedback_toggler.cc
index 7b7d0d5279f57c697fd55ab92b82a487ef81ed59..e62e75c1365693d290101871a42563d16a10d2ed 100644
--- a/ash/accelerators/spoken_feedback_toggler.cc
+++ b/ash/accelerators/spoken_feedback_toggler.cc
@@ -53,7 +53,7 @@ bool SpokenFeedbackToggler::ShouldStopEventPropagation() const {
 void SpokenFeedbackToggler::OnKeyHold(const ui::KeyEvent* event) {
   if (!toggled_) {
     toggled_ = true;
-    WmShell::Get()->GetAccessibilityDelegate()->ToggleSpokenFeedback(
+    WmShell::Get()->accessibility_delegate()->ToggleSpokenFeedback(
         A11Y_NOTIFICATION_SHOW);
   }
 }