Wire up the appearance and the transient state of system bars between
WMS and System UI. The derived classes of CommandQueue.Callbacks no
longer listen to setSystemUiVisibility, but listen to showTransient,
abortTransient, and onSystemBarAppearanceChanged instead.
Bug: 118118435
Test: atest InsetsSourceProviderTest InsetsStateControllerTest
InsetsPolicyTest WindowStateTests CommandQueueTest
RegisterStatusBarResultTest InsetsFlagsTest
LightBarControllerTest
Test: build on specific target
Change-Id: Ie35f4b4468bce7ef8c76f091e306610c069fba85
956ca413e3