exo: Use WMHelper to access ash accessibility related features.

components/exo/shell_surface_unittest.cc

Index: components/exo/shell_surface_unittest.cc
diff --git a/components/exo/shell_surface_unittest.cc b/components/exo/shell_surface_unittest.cc
index 38d221fc4ca330f38b3a640c5728f78e28a0752d..b037a2fb3c34c5f4caebca16aeb57fa12839dfe0 100644
--- a/components/exo/shell_surface_unittest.cc
+++ b/components/exo/shell_surface_unittest.cc
@@ -726,7 +726,7 @@ TEST_F(ShellSurfaceTest, SpokenFeedbackFullscreenBackground) {
   // Enable spoken feedback.
   ash::WmShell::Get()->accessibility_delegate()->ToggleSpokenFeedback(
       ash::A11Y_NOTIFICATION_NONE);
-  shell_surface.OnAccessibilityModeChanged(ash::A11Y_NOTIFICATION_NONE);
+  shell_surface.OnAccessibilityModeChanged();
 
   EXPECT_EQ(display::Screen::GetScreen()->GetPrimaryDisplay().bounds(),
             shell_surface.shadow_underlay()->bounds());
@@ -762,8 +762,8 @@ TEST_F(ShellSurfaceTest, SpokenFeedbackFullscreenBackground) {
   // Disable spoken feedback. Shadow underlay is restored.
   ash::WmShell::Get()->accessibility_delegate()->ToggleSpokenFeedback(
       ash::A11Y_NOTIFICATION_NONE);
-  shell_surface.OnAccessibilityModeChanged(ash::A11Y_NOTIFICATION_NONE);
-  shell_surface2.OnAccessibilityModeChanged(ash::A11Y_NOTIFICATION_NONE);
+  shell_surface.OnAccessibilityModeChanged();
+  shell_surface2.OnAccessibilityModeChanged();
 
   EXPECT_TRUE(shell_surface.shadow_underlay()->IsVisible());
   EXPECT_EQ(shadow_bounds, shell_surface.shadow_underlay()->bounds());