CQ: ignore changes that have been modified w/in the last 5 minutes.
CQ: ignore changes that have been modified w/in the last 5 minutes.

This is primarily done so that CQ doesn't pick up a change that has
dependencies that haven't yet been marked CR (but are in the process
of being marked).  Additionally, this has the benefit of making CQ
ignore changes that are currently getting noise on them- whether
via people uploading fresh changes, or due to people questioning
the commit readyness.

BUG=chromium-os:24737
TEST=grab the query, fiddle w/ the age setting for experimentation.
TEST=run_tests.sh

Change-Id: Ib92af5fb2daba6fd55ee5d02992b64a05a74069e
Reviewed-on: https://gerrit.chromium.org/gerrit/16999
Tested-by: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>
Reviewed-by: Chris Sosa <959d3d631fb6f17f1b07f751372041a1edb210d1@chromium.org>
Commit-Ready: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>

zhang0137/chromite,coreos/chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,zhang0137/chromite,bpsinc-native/src_third_party_chromite,zhang0137/chromite,coreos/chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite