Silence --trace-turbo a bit and behave graceful in sandbox.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/786763002

Cr-Commit-Position: refs/heads/master@{#25709}
Update all DEPS to match chromium's DEPS at edb488e

Also remove the now disfunctinal 'builddeps' and 'dependencies' targets

BUG=none
R=machenbach@chromium.org,jkummerow@chromium.org
LOG=y

Review URL: https://codereview.chromium.org/788613002

Cr-Commit-Position: refs/heads/master@{#25710}