Implement smoother swipe animation for Phone UI

Phone UI conditionally shows split ActionBar on the bottom,
which makes swipe animation less smooth. This change makes it
smoother by reducing layout re-calculation.

- stop changing menu state on onPageSelected but do so on
  onPageScrollStateChange.
- use android:windowActionBarOverlay to suppress recalculation
  during menu show-up
- add marginTop to every fragment for Phone so that fragments
  won't overlap with ActionBar
- add paddingBottom for CallLog and Favorites so that those
  fragments won't overlap with split ActionBar

FUTURE TODO:

We need custom assets for android:actionBarStyle
- android:background
- android:backgroundStacked
- android:backgroundSplit

Bug: 5022052
Change-Id: I3bd48cf9d8aaa398806531823fca63de328b807a
7 files changed