add virtual device known failures expectation file

* the file contains tests known to fail on virtual devices, due
  to limitation of its test infra setup

Bug: 30965313
Bug: 31429663
Test: ...
  $ unzip -l \
    out/host/linux-x86/cts/android-cts/testcases/CtsLibcoreTestCases.apk \
    | grep virtualdevice # check for existence
  BEFORE: $ cts-tradefed run collect-tests-only \
    --include-filter CtsLibcoreTestCases
  AFTER: $ cts-tradefed run collect-tests-only \
    --include-filter CtsLibcoreTestCases \
    --compatibility:module-arg \
    CtsLibcoreTestCases:core-expectation:/virtualdeviceknownfailures.txt
  Compare generated test list to make sure listed test is excluded

Change-Id: I0bbe0acbf2823429b831c0a33475fe297c338c9a
1 file changed