Fix regular sync, part 1.

- Add support for new IEmailService#sync.
- Don't pass SyncResult through EasOperations. This was
  probably a bad idea to begin with. Instead, callers that
  care should use performOperation()'s return value to set
  the results appropriately.
- Fix upsync operations to signal request/network errors
  ASAP (and mark any unperformed upsyncs as retries).
- In ESAS, bail early on first error.
- In ESAS, set up forwarding to EasService for pushModify.
- Converting mail downsync into an EasOperation. For now,
  not merging it with the EasSync class that already exists.

Change-Id: I4719c5cafbd01a957f267b221cf3276010154176

14 files changed