Migrating SettingsLib tests to /external/robolectic.

FragmentController was a hack added to Android's /external/robolectric-shadows.
Moving that debt to /framework/base sub repos.
Updating testutils to new robolectric restrictions.
Using the OverpowerReflectionHelpers where required.

Shadows that look to have issues:

* ShadowViewRootImpl.callDispatchResized (needs updated for U)

Bug: 261728063
Test: atest SettingsLibRoboTests
Change-Id: If1ad79c35d3038016115ce5af8c9554d6d0502de