Eclipse plugin :no menu in Extension when right clicks

I'm looking at eclipse plugin and I met a problem in extension view : I can't access to the extension menu when I did right click.

I have also the following warning in Extensions View : No schema found for the “org.eclipse.ui.menus” extension point

To solves it,  I add Eclipse RCP Target Components ( see http://stackoverflow.com/questions/8366303/no-schema-found-for-the-org-eclipse-ui-menus-extension-point )

1. In Eclipse, go to Help > Install New Software... 
2. Update site: http://download.eclipse.org/eclipse/updates/4.5
3. Choose "Eclipse RCP Target Components" and press Next to install them

Now the menu appears :




Eclipse IDE for Java Developers
Version: Mars Release (4.5.0)