Remove PassphraseType param from SyncService::SetEncryptionPassphrase

The passphrase type had two possible values, EXPLICIT and IMPLICIT.
IMPLICIT is an ancient legacy concept that hasn't been used in many
years, apart from tests: ProfileSyncServiceHarness did use it in some
circumstances. It's a bad idea to have tests go through an
otherwise-dead code path, so this CL removes those calls.

Bug: 865936
Cq-Include-Trybots: luci.chromium.try:ios-simulator-cronet;luci.chromium.try:ios-simulator-full-configs
Change-Id: Ib91570265eccbe8831e4c831ad9d5dc3c7a6cc18
Reviewed-on: https://chromium-review.googlesource.com/c/1280268
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Reviewed-by: David Roger <droger@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599891}
17 files changed