Bug 313459 Problem with % when generating images in tables.
See the attached BirtProject, it has two reports. Each identical except for this difference: The image width/height is set to a %age value (50%) in one (TestImage.rptdesign) and not-set in the other (TestImageWorking.rptdesign). TestImage.rptdesign does not display the image in pdf, but works fine in html. TestImageWorking.rptdesign shows the image in both pdf and html. The %age setting seems to cause the problem in pdf format.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/util/PropertyUtil.java
else if ( units.equals( EngineIRConstants.UNITS_EM )
					|| units.equals( EngineIRConstants.UNITS_EX ) )
			{
				int size = 9000;
				if ( content != null )
				{
					IStyle style = content.getComputedStyle( );
					CSSValue fontSize = style
							.getProperty( IStyle.STYLE_FONT_SIZE );
					size = getDimensionValue( fontSize );
				}
				double point = size * d.getMeasure( );
				return (int) point;
			}
		}
		else if ( d.getValueType( ) == DimensionType.TYPE_CHOICE )
		{
			String choice = d.getChoice( );
			if ( IStyle.CSS_MEDIUM_VALUE.equals( choice ) )
			{
				return 3000;
			}
			else if ( IStyle.CSS_THIN_VALUE.equals( choice ) )
			{
				return 1000;
			}
			else if ( IStyle.CSS_THICK_VALUE.equals( choice ) )
			{
				return 5000;
			}