src/vs/workbench/api/common/extHostQuickOpen.ts/ExtHostQuickOpenImpl/createQuickPick
class ExtHostQuickOpenImpl:		createQuickPick<T extends QuickPickItem>(extensionId: ExtensionIdentifier, enableProposedApi: boolean): QuickPick<T> {
			const session: ExtHostQuickPick<T> = new ExtHostQuickPick(extensionId, enableProposedApi, () => this._sessions.delete(session._id));
			this._sessions.set(session._id, session);
			return session;
		}