Revert "ugly fix: if stdout is missing after cloud-execution, do not abort, but use 0 as returnvalue and warn the user. This allows to parse the logfile for status and stats, even if measuring failed in the cloud."

This reverts r13809.

Of course, we prefer a real solution,
and not one that adds fake values to the result tables.

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@13815 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c