Fix error detection & exit in report_results

We wish to fail if we have >0 zero errors, not >1 errors (i.e. exactly
one error did not trigger a failure!)

This change also brings consistency to the pass & failure paths by
ensuring report_results exits in both cases, since report_results is
supposed to be the last thing run in a test file.

Change-Id: Id4721dffe13721e6c3cd71bca40c3395627e98bf

Author: ianw

tests/unittest.sh

@@ -92,16 +92,17 @@ function assert_empty {
     fi
 }
 
-# print a summary of passing and failing tests, exiting
-# with an error if we have failed tests
+# Print a summary of passing and failing tests and exit
+# (with an error if we have failed tests)
 #  usage: report_results
 function report_results {
     echo "$PASS Tests PASSED"
-    if [[ $ERROR -gt 1 ]]; then
+    if [[ $ERROR -gt 0 ]]; then
         echo
         echo "The following $ERROR tests FAILED"
         echo -e "$FAILED_FUNCS"
         echo "---"
         exit 1
     fi
+    exit 0
 }