On Debian's default install curl is not available, but wget is.

Bug: 762568
Change-Id: Ibc8c52676fd5e37ef1b9f1ffc061b2be27ec80c4
Reviewed-on: https://chromium-review.googlesource.com/653517Reviewed-by: Daniel Jacques <dnj@chromium.org>
Commit-Queue: Paweł Hajdan Jr. <phajdan.jr@chromium.org>