Previous changes have applied mechanical refactorings, but this change
hand-migrates the remaining logic which was too complex to identify.
This change should have no behavior change; famous last words.
Bug: 171832118
Test: manual
Exempt-From-Owner-Approval: trivial refactoring
Change-Id: I85cd830eb6bfde18fca6e73ee7adfdc385a890de
a2c132d9c6