Catch and report errors if the testEnv script fails.
Catch and report errors if the testEnv script fails.

Report an error if the testEnv script does not return a number.  I'm
sure there are more cases like this one, but now they should be caught
by start_test (r19538) so we can fix them as we run into them.

Tom is working on fixing the testEnv script.



git-svn-id: 88467cb1fb04b8a755be7e1ee1026be4190196ef@19539 3a8e244f-b0f2-452b-bcba-4c88e055c3ca

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