fix: remove undo and redo shortcuts in favor of those in core (#628)

Author: maribethb

src/actions/undo_redo.ts

@@ -35,7 +35,6 @@ import {DisconnectAction} from './actions/disconnect';
 import {ActionMenu} from './actions/action_menu';
 import {MoveActions} from './actions/move';
 import {Mover} from './actions/mover';
-import {UndoRedoAction} from './actions/undo_redo';
 
 const KeyCodes = BlocklyUtils.KeyCodes;
 
@@ -69,8 +68,6 @@ export class NavigationController {
 
   enterAction: EnterAction = new EnterAction(this.mover, this.navigation);
 
-  undoRedoAction: UndoRedoAction = new UndoRedoAction();
-
   actionMenu: ActionMenu = new ActionMenu(this.navigation);
 
   moveActions = new MoveActions(this.mover);
@@ -244,7 +241,6 @@ export class NavigationController {
     this.exitAction.install();
     this.enterAction.install();
     this.disconnectAction.install();
-    this.undoRedoAction.install();
     this.actionMenu.install();
 
     this.clipboard.install();
@@ -270,7 +266,6 @@ export class NavigationController {
     this.arrowNavigation.uninstall();
     this.exitAction.uninstall();
     this.enterAction.uninstall();
-    this.undoRedoAction.uninstall();
     this.actionMenu.uninstall();
     this.shortcutDialog.uninstall();