Replace ShadeRepository.shadeModel

All usage could be satisfied by legacyShadeExpansion. That flow is
deprecated, but using allows us to delete ShadeExpansionStateManager.

Bug: 269323368
Test: Verified identical expansion values were emitted by the 2 flows
Test: Updated and ran existing tests
Flag: NONE
Change-Id: I41150dada9ffaa1d4c9d6436a123db3a83a64481