Bug 147687 Assert err happened with design ui
Run BIRT in workbench with argument -ea. Assert err happened when using design ui to open a design file.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dialogs/ExpressionTreeSupport.java
textData.append( className + "." );
		}
		textData.append( info.getName( ) );
		return textData.toString( );
	}
	private boolean isStatic( ILocalizableInfo info )
	{
		return info instanceof IMethodInfo
				&& ( (IMethodInfo) info ).isStatic( )
				|| info instanceof IMemberInfo
				&& ( (IMemberInfo) info ).isStatic( );
	}
	public void createContextCatagory( )
	{
		Assert.isNotNull( tree );
		contextItem = createTopTreeItem( tree, TREE_ITEM_CONTEXT );
		createContextObjects( currentMethodName );
	}
	/**
	 * Creates context objects tree. Context ojects tree is used in JS editor
	 * palette, which displays current object method's arguments.
	 */
	public void createContextObjects( String methodName )
	{
		if ( contextItem != null
				&& !contextItem.isDisposed( )
				&& currentEditObject != null
				&& methodName != null )
		{
			removeTreeItem( );