[Status Bar] Store disable flag calculations in a data class.

The disable flags are split into two ints and are difficult to reason
about because they're negative booleans and involve bitwise logic.

This immediately converts the disable flags into a data class object
with clear naming and positive booleans.

Fixes: 279899176
Test: atest CollapsedStatuBarFragmentTest (existing tests are mostly
sufficient, added a few additional ones)
Test: atest StatusBarVisibilityModelTest
Test: verify status bar still hidden on keyguard
Test: verify clock & notif icons hidden when there's a HUN
Test: verify notif icons hidden when there's an ongoing call
Test: verify CollapsedSbFragmentLog statements

Change-Id: If0d82a5be1858d71a68e2c1aeda9c790be229168