src/vs/workbench/api/browser/mainThreadOutputService.ts/MainThreadOutputService/$close
class MainThreadOutputService:	public $close(channelId: string): Promise<void> | undefined {
		if (this._viewsService.isViewVisible(OUTPUT_VIEW_ID)) {
			const activeChannel = this._outputService.getActiveChannel();
			if (activeChannel && channelId === activeChannel.id) {
				this._viewsService.closeView(OUTPUT_VIEW_ID);
			}
		}

		return undefined;
	}