Renames WmWindowUserData and converts to using aura

ash/wm/screen_dimmer_unittest.cc

Index: ash/wm/screen_dimmer_unittest.cc
diff --git a/ash/wm/screen_dimmer_unittest.cc b/ash/wm/screen_dimmer_unittest.cc
index 709886f738be2e07edcb986af69f8b8416e570f8..24bd2b042915446e90aa51a52adac727f47372f8 100644
--- a/ash/wm/screen_dimmer_unittest.cc
+++ b/ash/wm/screen_dimmer_unittest.cc
@@ -9,7 +9,6 @@
 #include "ash/common/wm/window_dimmer.h"
 #include "ash/common/wm_shell.h"
 #include "ash/common/wm_window.h"
-#include "ash/common/wm_window_user_data.h"
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
@@ -37,9 +36,8 @@ class ScreenDimmerTest : public AshTestBase {
 
   aura::Window* GetDimWindow() {
     WindowDimmer* window_dimmer =
-        dimmer_->window_dimmers_->Get(WmShell::Get()->GetPrimaryRootWindow());
-    return window_dimmer ? WmWindow::GetAuraWindow(window_dimmer->window())
-                         : nullptr;
+        ScreenDimmer::GetWindowDimmer(Shell::GetPrimaryRootWindow());
+    return window_dimmer ? window_dimmer->window() : nullptr;
   }
 
   ui::Layer* GetDimWindowLayer() {