Bug 299212 [Preferences] BIDI_BDL: Incorrect path display in Linked Resources list of Preferences dialog
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/PathVariablesGroup.java
*/
    private String removeParentVariable(String value) {
    	return pathVariableManager.convertToUserEditableFormat(value, false);
    }
    
    /**
     * Commits the temporary state to the path variable manager in response to user
     * confirmation.
     * @return boolean <code>true</code> if there were no problems.
     * @see IPathVariableManager#setValue(String, IResource, URI)
     */
    public boolean performOk() {
        try {
              
            for (Iterator removed = removedVariableNames.iterator(); removed
                    .hasNext();) {
                String removedVariableName = (String) removed.next();
                
                if (!tempPathVariables.containsKey(removedVariableName)) {
					pathVariableManager.setValue(removedVariableName, currentResource, null);
				}
            }
            
            for (Iterator current = tempPathVariables.entrySet().iterator(); current
                    .hasNext();) {
                Map.Entry entry = (Map.Entry) current.next();
                String variableName = (String) entry.getKey();
                IPath variableValue = (IPath) entry.getValue();
                if (!isBuiltInVariable(variableName))
                    pathVariableManager.setValue(variableName, currentResource, URIUtil.toURI(variableValue));