Bug 182076 Delete a style from a report item doesn't affect report xml source
Steps to reproduce: 1.Insert a label onto layout; 2.New a style, suppose named it "NewStyle"; 3.Right click the label and on the drop down list, choose Style->Apply Style->NewStyle; 4.Save the report design; 5.Right click the label and on the drop down list, choose Style->Delete Style->NewStyle; 6.Save the report design; Expected result: NewStyle is deleted from report design, and the label doesn't have the style property. Actual result: Switch to report xml source, a error mark indicate that the label still has a style property:<property name="style">NewStyle</property>
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/core/commands/DeleteCommand.java
source = DNDUtil.unwrapToModel( source );
		if ( source instanceof Object[] )
		{
			Object[] array = (Object[]) source;
			for ( int i = 0; i < array.length; i++ )
			{
				dropSource( array[i] );
			}
		}
		else if ( source instanceof StructuredSelection )
		{
			dropSource( ( (StructuredSelection) source ).toArray( ) );
		}
		else if ( source instanceof DesignElementHandle )
		{
			dropSourceElementHandle( (DesignElementHandle) source );
		}
		else if ( source instanceof EmbeddedImageHandle )
		{
			dropEmbeddedImageHandle( (EmbeddedImageHandle) ( source ) );
		}
		else if ( source instanceof SlotHandle )
		{
			dropSourceSlotHandle( (SlotHandle) source );
		}
		else if ( source instanceof CssStyleSheetHandle )
		{
			dropCssStyleHandle( (CssStyleSheetHandle) source );
		}
	}