Bug 85452 [IDE] (regression) Backdrop missing when all perspectives closed
I20050215-2300 - close all perspectives - the main page is blank - it should have a backdrop with text and button explaining how to open a perspective
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/IDEWorkbenchAdvisor.java
}
    /**
     * Returns the ordered map of versioned feature ids -> AboutInfo that are
     * new for this session.
     * 
     * @return ordered map of versioned feature ids (key type:
     *         <code>String</code>) -> infos (value type:
     *         <code>AboutInfo</code>).
     */
    public Map getNewlyAddedBundleGroups() {
        if (newlyAddedBundleGroups == null)
            newlyAddedBundleGroups = createNewBundleGroupsMap();
        return newlyAddedBundleGroups;
    }
    /**
     * Updates the old features setting and returns a map of new features.
     */
    private Map createNewBundleGroupsMap() {
        	
        IDialogSettings settings = IDEWorkbenchPlugin.getDefault()
                .getDialogSettings();
        String[] previousFeaturesArray = settings.getArray(INSTALLED_FEATURES);
        
        Map bundleGroups = computeBundleGroupMap();
        String[] currentFeaturesArray = new String[bundleGroups.size()];
        bundleGroups.keySet().toArray(currentFeaturesArray);
        settings.put(INSTALLED_FEATURES, currentFeaturesArray);
        
        if (previousFeaturesArray != null)
            for (int i = 0; i < previousFeaturesArray.length; ++i)