Note that there wasn't any case of multiple testcase classes in
1 file. All the cases reported in the issue were false positives
caused but other "mock/fixture" files being named _test.
So all this issue does is:
1) rename any _test suffixed class in test files, because we are
going to start renaming a lot of test classes to _test.
2) ensure that the 2 test case classes modified in this issue,
are already observing the filename = classname rule that will
be implemented soon (and verigy it works).
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