round-robin.sh: Fix un-intutive bash behavior

Turns out that condition in "if ${undefined_var+false}; then ... fi"
evaluated to "true" when $undefined_var is undefined -- i.e., empty
condition is a "true" condition, as long as it is not physically
empty ("if ; then ... fi" will produce a syntatic error).

This perculiarity of bash caused unexpected behavior and we used
"empty" branch of base-artifacts for several builds -- which,
unfortunately, caused us to loose history regressions in several
configurations.  We caught this quickly, so no serious damage done.

Fix by adding verbose conditionals.

Change-Id: Ib6f1a624a9ea41f7223bc3e85e2e4eddc3fad9a9

0 files changed, 0 insertions, 0 deletions