Skip Uprev/BuildImage stage properly with "Not running" message logged
Skip Uprev/BuildImage stage properly with "Not running" message logged

BUG=chromium:375492
TEST=`buildbot/run_tests` passes

Change-Id: Ibc1f3b72562892f1422481d6a6d665de3fbb2064
Reviewed-on: https://chromium-review.googlesource.com/200662
Reviewed-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Commit-Queue: Yu-Ju Hong <52dc720c411f8e2156e608c1a8b894a917489667@chromium.org>
Tested-by: Yu-Ju Hong <52dc720c411f8e2156e608c1a8b894a917489667@chromium.org>

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