Add activatable MenuItems

Activatable MenuItems will toggle their view's setActivated() state
every time they are clicked. In reference-design chassis, this means
they will turn black-on-white with a white circle background when activated.
OEMs can customize what the icons look like when activated, but individual
apps cannot.

Fixes: 142410396
Test: Manually
Change-Id: Ife3251b461e3d3a945d492490c613e9b490f87a5
15 files changed