GitLab

- kFileNotFound and kArraySizeZero now treated as kSuccess.
- Updated shared definitions in whitelist_packed_format source set.  New timestamp
to track last load attempt in local cache.  Added relative path and file name too.
- Decision made to check is_sorted on array during init.
The array will be smaller than in original design, so speed hit will be minimal.
- New tests.

BUG=769590
TEST=chrome_elf_unittests.exe, WhitelistFileTest.*

Change-Id: I45c4321ccdf89d8768509c0dad21c9c15f73c4e3
Reviewed-on: https://chromium-review.googlesource.com/794551
Commit-Queue: Penny MacNeil <pennymac@chromium.org>
Reviewed-by: Greg Thompson <grt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523544}