src/vs/base/browser/ui/splitview/paneview.ts/Pane/constructor
class Pane:	constructor(options: IPaneOptions) {
		super();
		this._expanded = typeof options.expanded === 'undefined' ? true : !!options.expanded;
		this._orientation = typeof options.orientation === 'undefined' ? Orientation.VERTICAL : options.orientation;
		this._ariaHeaderLabel = localize('viewSection', "{0} Section", options.title);
		this._minimumBodySize = typeof options.minimumBodySize === 'number' ? options.minimumBodySize : this._orientation === Orientation.HORIZONTAL ? 200 : 120;
		this._maximumBodySize = typeof options.maximumBodySize === 'number' ? options.maximumBodySize : Number.POSITIVE_INFINITY;

		this.element = $('.pane');
	}