Bug 175664 [Mac] Unexpected internal exception occurs when invoke expression builder
Description: There are two problems: 1. "fx" button (Click this button to invoke Expression Builder) could not be displayed correctly, nothing displayed in the button. 2. Click on the button, an unexpected internal exception occurs. Version:2.2.0.v20070205 Steps to reproduce: 1.Insert a Data item to the layout. Click "fx" button to invoke the expression builder, although on Mac "fx" button could not display correctly. Error log: Argument cannot be null Plug-in Provider: Eclipse.org Plug-in Name: BIRT Designer UI Plug-in ID: org.eclipse.birt.report.designer.ui Error Code: Error.GUIException.invokedByUnexpectedException Error Message:Argument cannot be null
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/util/UIUtil.java
return ( (GraphicalEditorWithFlyoutPalette) reportEditor.getActivePageInstance( ) ).getGraphicalViewer( );
	}
	/**
	 * Creates a new grid layout without margins by default
	 * 
	 * @return the layout created
	 */
	public static GridLayout createGridLayoutWithoutMargin( )
	{
		GridLayout layout = new GridLayout( );
		layout.marginHeight = layout.marginWidth = 0;
		return layout;
	}
	public static GridLayout createGridLayoutWithMargin( int margin )
	{
		GridLayout layout = new GridLayout( );
		layout.marginHeight = layout.marginWidth = margin;
		return layout;
	}
	/**
	 * Creates a new grid layout without margins with given the number of
	 * columns, and whether or not the columns should be forced to have the same
	 * width
	 * 
	 * @param numsColumn
	 *            the number of columns in the grid
	 * @param makeColumnsEqualWidth
	 *            whether or not the columns will have equal width
	 * 
	 * @return the layout created