Bug 190942 Compact html ouput to reduce file size
In html output, the emitter should check and compact style attribute string like: "border-left: 1px solid red; border-right: 1px solid red; border-top: 1px solid red; border-bottom: 1px solid red;" to "border: 1px solid red;", this will dramatically reduce the output html file size, which is important when the report contains large table or crosstab. This is also true for padding, margin and other style properties.
engine/org.eclipse.birt.report.engine.emitter.html/src/org/eclipse/birt/report/engine/emitter/html/AttributeBuilder.java
if (linethrough == IStyle.LINE_THROUGH_VALUE || underline == IStyle.UNDERLINE_VALUE || overline == IStyle.OVERLINE_VALUE)
		{
			content.append( " text-decoration:" ); 
			if (IStyle.LINE_THROUGH_VALUE == linethrough )
			{
				addPropValue( content, "line-through" );
			}
			if ( IStyle.UNDERLINE_VALUE == underline)
			{
				addPropValue( content, "underline" );
			}
			if ( IStyle.OVERLINE_VALUE == overline)
			{
				addPropValue( content, "overline" );
			}
			content.append( ';' );
		}
	}
	/**
	 * Build the border string.
	 * <li>ignore all the border styles is style is null
	 * <li>CSS default border-color is the font-color, while BIRT is black
	 * <li>border-color is not inheritable.
	 * 
	 * @param content
	 *            The <code>StringBuffer</code> to which the result is output.
	 * @param name
	 *            The proerty name.
	 * @param width
	 *            The border-width value.