Crazy Martin tried to import jtreg tests into CVS and got an obscure failure.
jtreg should be more tolerant of unexpected source code control system metadata.
This failure can be simulated with current jdk9-dev as follows:

jdk9-dev/jdk/test $ (mkdir -p java/util/stream/bootlib/CVS && /home/martin/jtreg-binaries/4.2-b05/bin/jtreg -verbose:nopass,fail,error -nr -testjdk:/home/martin/ws/jdk9-dev/build/linux-x86_64-normal-server-release/images/jdk java/util/Spliterator/SpliteratorCollisions.java)
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TEST: java/util/Spliterator/SpliteratorCollisions.java
TEST JDK: /home/martin/ws/jdk9-dev/build/linux-x86_64-normal-server-release/images/jdk

TEST RESULT: Error. Can't mix packages, user modules, and patches for system module in library: /home/martin/ws/jdk9-dev/jdk/test/java/util/stream/bootlib
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