build_image: Add a message for summary for brillo.

build_image produces a summary that is targeted at cros tools.
When using brillo image, build_image tells the user to use
cros flash which can be confusing. When brillo tools are used,
the summary now tells the user to use brillo flash instead of
cros flash.

The path to the image is now outside the chroot instead of
inside the chroot

BUG=brillo:1189
TEST=manual tests
CQ-DEPEND=CL:275702, CL:275726

Change-Id: I81428f718e23b76b3da2e07eb584f87e0400371c
Reviewed-on: https://chromium-review.googlesource.com/275748
Reviewed-by: Steve Fung <stevefung@chromium.org>
Commit-Queue: Ralph Nathan <ralphnathan@chromium.org>
Trybot-Ready: Ralph Nathan <ralphnathan@chromium.org>
Tested-by: Ralph Nathan <ralphnathan@chromium.org>
1 file changed