Move data loading and account creation to edit contact base class

While moving things from ContactEditorFragment to ContactEditorBaseFragment:

* The data loader callbacks, #onActivityCreated, #setData, and account
  creation methods were not changed in any way
* For the restoration of contact editor state, one small change was made.
  A new key, KEY_AUTO_ADD_TO_DEFAULT_GROUP, was added because the other
  options passed in via intentExtras argument to #load are saved
  so this looks like an oversight in the existing version.

Bug 19124091

Change-Id: I7973f9c5703082f6d8db53c9db22d08a230c5876