Bug 147676 [regression]Visibility set in the first col will affect the second col
Description: Visibility set in the first col will affect the second col Steps to reproduce: 1. Insert a grid(3*3), insert contents to each cell. 2.Set the first col to hide all in visibility and preview Expected result: Only the first col is hidden. Actual result: The second col is hidden, too. If you set the second col in step2, the third col will disappear.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/PDFTableLM.java
}
		}
	}
	protected void removeDropAreaBySpan( int rowSpan )
	{
		Iterator iter = dropList.iterator( );
		while ( iter.hasNext( ) )
		{
			DropCellInfo dropCell = (DropCellInfo) iter.next( );
			if ( dropCell.rowSpan == rowSpan )
			{
				verticalAlign( dropCell.cell );
				iter.remove( );
			}
		}
	}
	private int createDropID( int groupIndex, String dropType )
	{
		int dropId = -10 * ( groupIndex + 1 );
		if ( "all".equals( dropType ) ) 
		{
			dropId--;
		}
		return dropId;
	}
	/**
	 * start cell update content cache
	 * 
	 * @param cell
	 */