Enable jumbo for media/mojo

Building //media takes around 23 CPU minutes. A experimental
branch showed that this could be reduced, by using jumbo,
to around 9 CPU minutes. media/mojo is the largest part
of media and takes around 5 CPU minutes to compile without

This commit enables jumbo for media/mojo.

Bug: 867350
Change-Id: Iad7e5957cc7f01110c4163c9d368f1f04496630a
Reviewed-on: https://chromium-review.googlesource.com/1149863
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Oscar Johansson <oscarj@opera.com>
Cr-Commit-Position: refs/heads/master@{#578232}
3 files changed