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/parser/EngineIRVisitor.java
if ( testExpr != null && testExpr.length( ) > 0 )
		{
			rule.setTestExpression( testExpr );
		}
		else if ( ( defaultStr != null ) && defaultStr.length( ) > 0 )
		{
			rule.setTestExpression( defaultStr );
		}
		else
		{
			
			return null;
		}
		return rule;
	}
	/**
	 * Checks if a given style is in report's style list, if not, assign a
	 * unique name to it and then add it to the style list.
	 * 
	 * @param style
	 *            The <code>StyleDeclaration</code> object.
	 * @return the name of the style.
	 */
	private String assignStyleName( StyleDeclaration style )
	{
		if ( style == null || style.isEmpty( ) )
		{
			return null;
		}