src/vs/workbench/api/common/extHostQuickOpen.ts/ExtHostQuickOpenImpl/$onDidTriggerItemButton
class ExtHostQuickOpenImpl:		$onDidTriggerItemButton(sessionId: number, itemHandle: number, buttonHandle: number): void {
			const session = this._sessions.get(sessionId);
			if (session instanceof ExtHostQuickPick) {
				session._fireDidTriggerItemButton(itemHandle, buttonHandle);
			}
		}