src/vs/workbench/contrib/terminal/browser/terminalService.ts/TerminalService/_getSplitParent
class TerminalService:	private _getSplitParent(location?: ITerminalLocationOptions): ITerminalInstance | undefined {
		if (location && typeof location === 'object' && 'parentTerminal' in location) {
			return location.parentTerminal;
		} else if (location && typeof location === 'object' && 'splitActiveTerminal' in location) {
			return this.activeInstance;
		}
		return undefined;
	}