Bug 121498 When datasource/dataset deleted, the datasource/dataset property binding element haven't been deleted
When deleted the datasource/dataset, the datasource/dataset property binding element haven't been deleted. Expected result: This operation must be a transaction.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
{
			EmbeddedImage image = (EmbeddedImage) images.get( i );
			List clients = image.getClientStructures( );
			if ( clients == null || clients.isEmpty( ) )
				continue;
			for ( int j = 0; j < clients.size( ); j++ )
			{
				Structure client = (Structure) clients.get( j );
				StructRefValue value = (StructRefValue) client
						.getLocalProperty( this,
								ReferencableStructure.LIB_REFERENCE_MEMBER );
				assert value != null;
				value.unresolved( value.getName( ) );
				image.dropClientStructure( client );
				sendEvent = true;
			}
		}
		
		if ( sendEvent )
			broadcast( new PropertyEvent( this, Module.IMAGES_PROP ) );
	}
	/**
	 * Updates the element reference which refers to the given library.
	 * 
	 * @param target
	 *            the library whose element references are updated.
	 * @param slotId
	 *            the id of themes/styles slot
	 */
	private void updateReferenceableClients( DesignElement target, int slotId )