Pass arg --show-volume-status for desktop configs
Pass arg --show-volume-status for desktop configs

BUG=chromium-os:22080
TEST=With USE flag is_desktop, should see --show-volume-status in chrome://version

Change-Id: I846b77befb03bf200d2263225a6acff384a1bf4c
Reviewed-on: https://gerrit.chromium.org/gerrit/14745
Reviewed-by: Daniel Erat <69d56254d3d393520d06e9838c23c147a5fee7d9@chromium.org>
Reviewed-by: Achuith Bhandarkar <885eb1ed0dfe5e52160a872becbca30c7fb85e73@chromium.org>
Tested-by: Achuith Bhandarkar <885eb1ed0dfe5e52160a872becbca30c7fb85e73@chromium.org>
Commit-Ready: Achuith Bhandarkar <885eb1ed0dfe5e52160a872becbca30c7fb85e73@chromium.org>

chadversary/chromiumos.platform.login_manager,chadversary/chromiumos.platform.login_manager,chadversary/chromiumos.platform.login_manager