Bug 168026 Still use the existing data binding even though the aggregate is different
I had a table in which a data binding which aggregates on a group. When I insert a new data item in the report, although the expressions are same, it aggregates on All, then it refered to the existing data binding. The expected behavior would be a new data binding is created with different aggregates.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ReportItemHandle.java
* Gets a handle to deal with the item's width.
	 * 
	 * @return a DimensionHandle for the item's width.
	 */
	public DimensionHandle getWidth( )
	{
		return super.getDimensionProperty( IReportItemModel.WIDTH_PROP );
	}
	/**
	 * Gets a handle to deal with the item's height.
	 * 
	 * @return a DimensionHandle for the item's height.
	 */
	public DimensionHandle getHeight( )
	{
		return super.getDimensionProperty( IReportItemModel.HEIGHT_PROP );
	}
	/**
	 * Returns the bookmark of the report item.
	 * 
	 * @return the book mark as a string
	 */
	public String getBookmark( )
	{
		return getStringProperty( IReportItemModel.BOOKMARK_PROP );
	}
	/**
	 * Sets the bookmark of the report item.
	 * 
	 * @param value