Small cleanups to CrostiniManager style

This CL tidies CrostiniManager a bit:
- Updates outdated comments referring to vm_name/container_name now that
we have the ContainerId type
- Removes some typedefs of callbacks that only add indirection making it
harder to follow
- Remove redundant comments like '// Notify observers'
- Explicitly number CrostiniResult enum values as they are displayed to
the user in some cases

Change-Id: I1bd300c338e4d7080b25062babeff9e656522158
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1679066
Reviewed-by: Joel Hockey <joelhockey@chromium.org>
Commit-Queue: Timothy Loh <timloh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#672749}
2 files changed