Lazily load the zip archiver's NaCl module.

The zip archiver component extension already handles lazy loading of the
NaCl module, but it was also unnecessarily loading it on startup.

BUG=889703

Change-Id: I7346a13d4a317cd62e6b7a0f3e41870b723be28e
Reviewed-on: https://chromium-review.googlesource.com/1248343
Reviewed-by: Noel Gordon <noel@chromium.org>
Commit-Queue: Anand Mistry <amistry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#594919}
2 files changed