Rename DisplayConfiguratorAnimation to DisplayAnimator

Also cleans up the class to new style guide some.

BUG=576375

Review URL: https://codereview.chromium.org/1590463004

Cr-Commit-Position: refs/heads/master@{#369893}
diff --git a/ash/test/shell_test_api.h b/ash/test/shell_test_api.h
index 654e425..b144f0b 100644
--- a/ash/test/shell_test_api.h
+++ b/ash/test/shell_test_api.h
@@ -37,7 +37,7 @@
   DragDropController* drag_drop_controller();
   AppListController* app_list_controller();
   MaximizeModeWindowManager* maximize_mode_window_manager();
-  void DisableDisplayConfiguratorAnimation();
+  void DisableDisplayAnimator();
 
   // Set ShelfDelegate.
   void SetShelfDelegate(ShelfDelegate* delegate);