[Sync] Clean up PSS boolean getters for consistency.
When cleaning up ProfileSyncServiceAndroid I noticed these inconsistencies
but it seemed like PSS was the one that should be changed, not PSSA.
Renames:
- EncryptEverythingEnabled -> IsEncryptEverythingEnabled
- EncryptEverythingAllowed -> IsEncryptEverythingAllowed
- FirstSetupInProgress -> IsFirstSetupInProgress
- backend_initialized -> IsBackendInitialized
- setup_in_progress -> IsSetupInProgress
BUG=497518
TBR=rogerta,stevenjb,pam,sdefresne
Review URL: https://codereview.chromium.org/
1321903005
Cr-Commit-Position: refs/heads/master@{#348178}