code: function() {
  		if( this.isInitialised === false ) {
  			return;
  		}
  		this._onUnload();
  		$( window ).off( 'resize', this._resizeFunction );
  		$( window ).off( 'unload beforeunload', this._unloadFunction );
  		this.root.callDownwards( '_$destroy', [], true );
  		this.root.contentItems = [];
  		this.tabDropPlaceholder.remove();
  		this.dropTargetIndicator.destroy();
  		this.transitionIndicator.destroy();
  		this.eventHub.destroy();
  
  		this._dragSources.forEach( function( dragSource ) {
  			dragSource._dragListener.destroy();
  			dragSource._element = null;
  			dragSource._itemConfig = null;
  			dragSource._dragListener = null;
  		} );
  		this._dragSources = [];
  	}
docs: Destroys the LayoutManager instance itself as well as every ContentItem
  within it. After this is called nothing should be left of the LayoutManager.
  
  @public
  @returns {void}