This allows app fragment use a less heavyweight fragment as super class
if they don't need PreferenceFragment. Using this class as base is
generally easier to set up robolectric tests too.
Bug: 33354536
Test: RunSettingsRoboTests
Change-Id: I91c4d242ea0333c76c8767c03c3f18dee6b6e104
Bug: 30681771
Test: SettingsUnitTests
Refactor visibility logging from InstrumentedFragment into a mixin. And
apply mixin in remaining fragments.
Change-Id: Ibbb59904336254a3e4bb9e8c7d0b36e5a6bc2622
SettingsPreferenceFragment has this already set so that the drawer
layout will work when the menu doesn't exist. However, some fragments
are not preference fragments, and we need to set setHasOptionsMenu
manually.
bug:27879503
Change-Id: I6faadeb56dab00af611ac413109800822038c66d