Give MWAlienExtensionInspector its title back

It was falling back to the default ve.ui.Inspector title
message, which doesn't exist. The message was right there in
the i18n file, it just wasn't being used.

Change-Id: I0676829d5787fa0f1d7ed7481b1dc55437237dd4
Merge "Give MWAlienExtensionInspector its title back"