Changing ZipFileInstaller to use the Unzip service.

As part of the effort to deprecate UtilityProcessHost, changing
extensions::UnzipInstaller to use the new Unzip service instead of
UtilityProcessMojoClient.

This remove the last use of a utility process for extensions, and as a
result the extensions/utility directory can be removed.

Tbr: tsepez@chromium.org,finnur@chromium.org
Bug: 799220
Change-Id: Ibe4c7f0c16909c99ed572822718ac56a6bcb57fa
Reviewed-on: https://chromium-review.googlesource.com/937902
Reviewed-by: Jay Civelli <jcivelli@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Reviewed-by: Ken Rockot <rockot@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Joshua Pawlicki <waffles@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Commit-Queue: Jay Civelli <jcivelli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542303}
34 files changed