mash: Migrate AccessibilityDelegate access to WmShell.

ash/magnifier/magnification_controller.cc

Index: ash/magnifier/magnification_controller.cc
diff --git a/ash/magnifier/magnification_controller.cc b/ash/magnifier/magnification_controller.cc
index c61f998afc27011449734e2e5b680c010507db4e..a0fc54a74b5d0802552a606fbaf05d6b134cd3fa 100644
--- a/ash/magnifier/magnification_controller.cc
+++ b/ash/magnifier/magnification_controller.cc
@@ -11,6 +11,7 @@
 #include "ash/common/accessibility_delegate.h"
 #include "ash/common/ash_switches.h"
 #include "ash/common/system/tray/system_tray_delegate.h"
+#include "ash/common/wm_shell.h"
 #include "ash/display/root_window_transformers.h"
 #include "ash/host/ash_window_tree_host.h"
 #include "ash/host/root_window_transformer.h"
@@ -564,8 +565,7 @@ void MagnificationControllerImpl::SetScale(float scale, bool animate) {
     return;
 
   ValidateScale(&scale);
-  Shell::GetInstance()->accessibility_delegate()->SaveScreenMagnifierScale(
-      scale);
+  WmShell::Get()->GetAccessibilityDelegate()->SaveScreenMagnifierScale(scale);
   RedrawKeepingMousePosition(scale, animate);
 }
 
@@ -591,15 +591,14 @@ void MagnificationControllerImpl::SetScrollDirection(
 }
 
 void MagnificationControllerImpl::SetEnabled(bool enabled) {
-  Shell* shell = Shell::GetInstance();
   ui::InputMethod* input_method = GetInputMethod(root_window_);
   if (enabled) {
     if (!is_enabled_ && input_method)
       input_method->AddObserver(this);
 
-    float scale = Shell::GetInstance()
-                      ->accessibility_delegate()
-                      ->GetSavedScreenMagnifierScale();
+    WmShell* wm_shell = WmShell::Get();
+    float scale =
+        wm_shell->GetAccessibilityDelegate()->GetSavedScreenMagnifierScale();
     if (scale <= 0.0f)
       scale = kInitialMagnifiedScale;
     ValidateScale(&scale);
@@ -610,7 +609,7 @@ void MagnificationControllerImpl::SetEnabled(bool enabled) {
 
     is_enabled_ = enabled;
     RedrawKeepingMousePosition(scale, true);
-    shell->accessibility_delegate()->SaveScreenMagnifierScale(scale);
+    wm_shell->GetAccessibilityDelegate()->SaveScreenMagnifierScale(scale);
   } else {
     // Do nothing, if already disabled.
     if (!is_enabled_)