Bug 104986 Backgound image uses an absolute path
Currently Chart uses an absolute path to indicate a backgournd image, that may cause the design unusable on other environments. Expected the background image can be definded in multiple ways like in report designer. e.g. URI(absolute path), File(relative path), Embedded Image(Encoded Image Data).
chart/org.eclipse.birt.chart.ui.extension/src/org/eclipse/birt/chart/ui/swt/composites/MarkerIconDialog.java
label.setLayoutData( new GridData( GridData.VERTICAL_ALIGN_BEGINNING ) );
		Composite selectionArea = new Composite( composite, SWT.NONE );
		selectionArea.setLayout( new FillLayout( SWT.VERTICAL ) );
		btnURL = new Button( selectionArea, SWT.RADIO );
		btnURL.setText( Messages.getString( "MarkerIconDialog.Lbl.URL" ) ); 
		btnURL.addSelectionListener( this );
		btnLocal = new Button( selectionArea, SWT.RADIO );
		btnLocal.setText( Messages.getString( "MarkerIconDialog.Lbl.Local" ) ); 
		btnLocal.addSelectionListener( this );
	}
	
	/**
	 * List Area locates in the left middle of the dialog.
	 * 
	 * @param parent
	 * 				dialog composite
	 */
	private void createListArea( Composite parent )
	{
		Composite listArea = new Composite( parent, SWT.NONE );
		GridData gd = new GridData( GridData.FILL_BOTH
				| GridData.HORIZONTAL_ALIGN_BEGINNING );
		gd.widthHint = 300;
		gd.heightHint = 260;
		listArea.setLayoutData( gd );
		listArea.setLayout( new GridLayout( ) );
		GridLayout gl = new GridLayout( );
		gl.marginWidth = 0;
		gl.marginHeight = 0;