Support the creation of special pages with services injected

Support the creation of special pages with services injected

Now that the ObjectFactory library supports object creation with
services (T222409), the special page factory can use the object
factory to create special pages based off a spec, allowing the
creation of special pages that need services injected.

The object factory now also handles constructing from class name
and from callable.

This also deprecates providing the special page list with an
instance of SpecialPage, which hasn't been necessary since
r15031.

Bug: T222388
Change-Id: Iabb78ce5c98cfb3b586644be35d984871cb750cb