Portage atom string must be the last line printed by cros_mark_chrome_as_stable.
Portage atom string must be the last line printed by cros_mark_chrome_as_stable.

Last Commit introduced a condition where if eclean / emerge --unmerge printed
to stdout, it would confused the buildbot.

Change-Id: Iece7f777efff205ed10884b6c8dc70f114f8ac4e

BUG=chromium-os:14639
TEST=Ran local instance of cbuildbot through to build stage.

Review URL: http://codereview.chromium.org/6905116

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