Bug 131258 NewOdaDataSet is created when drop dataset from data explorer into layout in library
Details: NewOdaDataSet is created when drop dataset from data explorer into layout in library Setp: 1.New a library 2.Create a datasource and dataset 3.Drop dataset from Actual result: A new dataset named NewOdaDataSet is created. Exception result: The dataset is unnecessary to be created
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/palette/BasePaletteFactory.java
{
		private List dataSetList = new ArrayList( );
		/*
		 * get target design element handle
		 * 
		 */
		private DesignElementHandle getDesignElementHandle( )
		{
			Object model = getTargetEditPart( ).getModel( );
			DesignElementHandle desginElementHandle = null;
			if ( model instanceof DesignElementHandle )
			{
				desginElementHandle = (DesignElementHandle) ( model );
			}
			else if ( model instanceof ListBandProxy )
			{
				desginElementHandle = ( (ListBandProxy) ( model ) ).getSlotHandle( )
						.getElementHandle( );
			}
			return desginElementHandle;
		}
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.birt.designer.internal.ui.editors.schematic.tools.IToolHandleExtends#preHandleMouseDown()