[Sync] Record orphaned metadata only if not deleted yet

This CL fixes a minor omission from a previous patch. It has minor
impact on recording the metric Sync.ModelTypeOrphanMetadata but since
this metric is out only for 5 days so far, this CL does not rename it.

While adding a new test, this CL also simplifies one existing test.

Bug: 1219615
Change-Id: Ie8af1da1d2bac49f087584350df59c1b8ce917e8
Reviewed-on: https://chromium-review.googlesource.com/1230030
Commit-Queue: Jan Krcal <jkrcal@chromium.org>
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#592055}
2 files changed