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
Composite composite = new Composite( cmpContent, SWT.NONE );
		composite.setLayout( new GridLayout( 2, false ) );
		createListArea( composite );
		createPreviewArea( composite );
		new Label( cmpContent, SWT.SEPARATOR | SWT.HORIZONTAL ).setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		Composite btnComposite = new Composite( cmpContent, SWT.NONE );
		btnComposite.setLayout( new GridLayout( 2, false ) );
		btnComposite.setLayoutData( new GridData( GridData.HORIZONTAL_ALIGN_END ) );
		btnOK = new Button( btnComposite, SWT.NONE );
		btnOK.setLayoutData( new GridData( GridData.HORIZONTAL_ALIGN_BEGINNING ) );
		btnOK.setText( Messages.getString( "Shared.Lbl.OK" ) ); 
		btnOK.addSelectionListener( this );
		btnOK.setEnabled( iconList.getSelectionCount( ) > 0 );
		btnCancel = new Button( btnComposite, SWT.NONE );
		btnCancel.setLayoutData( new GridData( GridData.HORIZONTAL_ALIGN_END ) );
		btnCancel.setText( Messages.getString( "Shared.Lbl.Cancel" ) ); 
		btnCancel.addSelectionListener( this );
	}
	/**
	 * Selection Area locates in the top of the dialog.
	 * 
	 * @param parent
	 * 				dialog composite
	 */
	private void createSelectionArea( Composite parent )
	{
		Composite composite = new Composite( parent, SWT.NONE );
		composite.setLayout( new GridLayout( 2, false ) );
		Label label = new Label( composite, SWT.NONE );
		label.setText( Messages.getString( "MarkerIconDialog.Lbl.SelectIconFrom" ) );