Move yet more from WmShell to Shell

ash/wm/panels/panel_window_resizer_unittest.cc

Index: ash/wm/panels/panel_window_resizer_unittest.cc
diff --git a/ash/wm/panels/panel_window_resizer_unittest.cc b/ash/wm/panels/panel_window_resizer_unittest.cc
index 3fd6e9e38cbdaf80e2abd76b64ccbba9ca11084e..438eae4c694c8ddaef9b94bfef823c8435fb62e5 100644
--- a/ash/wm/panels/panel_window_resizer_unittest.cc
+++ b/ash/wm/panels/panel_window_resizer_unittest.cc
@@ -41,7 +41,7 @@ class PanelWindowResizerTest : public test::AshTestBase {
   void SetUp() override {
     AshTestBase::SetUp();
     UpdateDisplay("600x400");
-    model_ = WmShell::Get()->shelf_model();
+    model_ = Shell::Get()->shelf_model();
   }
 
   void TearDown() override { AshTestBase::TearDown(); }