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
public static final String PARAM_IID = "iid"; 
	/**
	 * Parameter name that gives the result set names of the export data form.
	 */
	public static final String PARAM_RESULTSETNAME = "ResultSetName"; 
	/**
	 * Parameter name that gives the selected column numbers of the export data
	 * form.
	 */
	public static final String PARAM_SELECTEDCOLUMNNUMBER = "SelectedColumnNumber"; 
	/**
	 * Parameter name that gives the selected column names of the export data
	 * form.
	 */
	public static final String PARAM_SELECTEDCOLUMN = "SelectedColumn"; 
	/**
	 * Context parameter name that gives the default locale of the BIRT viewer.
	 */
	public static final String INIT_PARAM_LOCALE = "BIRT_VIEWER_LOCALE"; 
	/**
	 * Context parameter name that gives the working folder of the local BIRT
	 * viewer user.
	 */
	public static final String INIT_PARAM_WORKING_DIR = "BIRT_VIEWER_WORKING_FOLDER"; 
	/**
	 * Context parameter name that gives the repository location of the image
	 * files.
	 */
	public static final String INIT_PARAM_IMAGE_DIR = "BIRT_VIEWER_IMAGE_DIR"; 
	/**