[Bug 28609] New: msi/install.ok slightly flaky

http://bugs.winehq.org/show_bug.cgi?id=28609

Bug #: 28609
           Summary: msi/install.ok slightly flaky
           Product: Wine
           Version: 1.3.27
          Platform: x86
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]
    Classification: Unclassified

This happens about 1 out of 1000 runs:

../../../tools/runtest -q -P wine -M msi.dll -T ../../.. -p msi_test.exe.so
install.c && touch install.ok
...
install.c:4677: Tests skipped: Run in interactive mode to run source path
tests.
...
install.c:5391: Test failed: Directory not created
install.c:5407: Test failed: Directory not created

I first saw it last month.  It seemed to be happen a lot during the big rpcrt4
regression, but it's still happening, rarely, even though that's fixed now.

(Possibly related to bug 28257?)