Strict Null Checks, Builder Removal, Formatting (#4849)

* remove builder; more null checks

* null checks

* formatting

* wip

* fix dropdown themeing

* formatting

* formatting

* fix tests

* update what files are checked

* add code to help refresh bad nodes

src/sql/base/browser/ui/panel/tabActions.ts

@@ -2,6 +2,7 @@
  *  Copyright (c) Microsoft Corporation. All rights reserved.
  *  Licensed under the Source EULA. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
+
 import { Action } from 'vs/base/common/actions';
 import * as nls from 'vs/nls';
 
@@ -25,4 +26,4 @@ export class CloseTabAction extends Action {
 			return Promise.resolve(false);
 		}
 	}
-}
+}