There is no point calling AllocationSpaceName manually every time. We
could get rid of AllocationSpaceName entirely, except that the
serializer calls it directly on ints that are casted to AllocationSpace
objects first.

Change-Id: I26b2181347dba960c8523d5dcecf8128208c59a2
Reviewed-on: https://chromium-review.googlesource.com/1107816Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53888}