Bug 310446 [LinkedResources] "Preferences > Linked Resources > New..." should not show "Variable..."
I20100425-2000 "Preferences > Linked Resources": The "New..." and "Edit..." dialogs should not show the "Variable..." button. When I select a variable, the "New Variable" dialog show an error (Path must be absolute.), and when I try to click "Extend...", nothing happens.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/PathVariablesGroup.java
* @param value
     * @return the converted value
     */
    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.setURIValue(removedVariableName, 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();