Bug 176681 Issue about creating context-parameter path in read-only path[0601]
Description: Issue about creating context-parameter path in read-only path Build number:2.2.0.v20070308 Steps to reproduce: 1. Deploy birt. 2. Set BIRT_VIEWER_DOCUMENT_FOLDER/BIRT_VIEWER_IMAGE_DIR/.. to a read-only path. 3. Preview report. Expected result: Because the path is read-only, folders should be created in ${java.io.tmpdir} Actual result: No folders are created in ${java.io.tmpdir} and reports cannot be previewed in frameset mode.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
* @param request
	 * @return
	 */
	public static boolean isMasterPageContent( HttpServletRequest request )
	{
		boolean isMasterPageContent = true;
		if ( "false".equalsIgnoreCase( getParameter( request, PARAM_MASTERPAGE ) ) ) 
		{
			isMasterPageContent = false;
		}
		return isMasterPageContent;
	}
	/**
	 * Check whether report design will overwrite report doc or not.
	 * 
	 * @param request
	 * @return
	 */
	public static boolean isOverwrite( HttpServletRequest request )
	{
		boolean overwrite = isOverWrite;
		String urlParam = getParameter( request, PARAM_OVERWRITE );
		if ( "true".equalsIgnoreCase( urlParam ) ) 
		{
			overwrite = true;
		}
		else if ( "false".equalsIgnoreCase( urlParam ) ) 
		{
			overwrite = false;
		}