src/vs/workbench/contrib/snippets/browser/tabCompletion.ts/TabCompletionController/constructor
class TabCompletionController:	constructor(
		private readonly _editor: ICodeEditor,
		@ISnippetsService private readonly _snippetService: ISnippetsService,
		@IClipboardService private readonly _clipboardService: IClipboardService,
		@IContextKeyService contextKeyService: IContextKeyService,
	) {
		this._hasSnippets = TabCompletionController.ContextKey.bindTo(contextKeyService);
		this._configListener = this._editor.onDidChangeConfiguration(e => {
			if (e.hasChanged(EditorOption.tabCompletion)) {
				this._update();
			}
		});
		this._update();
	}