Bug 120345 Need a URL generator API from Engine
The Chart Engine needs the ability to generate a viewer URL from an ActionHandle, this can be provided by a Report Engine public API for instance. The URL should usable as is by the viewer without any additional change. The Chart Engine can take care of evaluating the expressions inside the ActionHandle before calling the Report Engine API if necessary.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/ExecutionContext.java
* execute script. call evaluate to evaluate the script and drop the return
	 * value
	 * 
	 * @param script
	 *            script to be executed.
	 */
	public void execute( IBaseExpression script )
	{
		if ( script != null )
		{
			evaluate( script );
		}
	}
	/**
	 * execute the script. Simply evaluate the script, then drop the return
	 * value
	 * 
	 * @param script
	 *            script statement
	 * @param fileName
	 *            file name
	 * @param lineNo
	 *            line no
	 */
	public void execute( String script, String fileName, int lineNo )
	{
		if ( script != null )
		{
			evaluate( script, fileName, lineNo );
		}