Use JUnit 4 annotation instead of 'large' tag for CTSv2

CTSv2 doesn't support tests tagged as 'large' having a
larger timeout; therefore, the move to CTSv2 broke tests
that do not reliably finish within 5min, such as
DHPublicKeyTest.

This CL converts the test to JUnit 4 in order to express
the timeout via JUnit 4 annotations. It also removes
DHPrivateKeyTest from the 'large' list without setting a
custom timeout since that test is only using a 192bit
rather than 1024bit key and is already much faster. The
more general problem of cleaning up other tests marked as
'large' appears beyond this CL's scope and was not done.

The fact that DHPublicKeyTest.test_getParams()'s run time
is so large and so variable is not clear; we should
investigate it in more detail when we have time.

Bug: 30741591
Test: cts-tradefed run cts -m CtsLibcoreTestCases -t \
org.apache.harmony.crypto.tests.javax.crypto.interfaces.DHPublicKeyTest
Test: Also ran DHPrivateKeyTest

Change-Id: Ia64bef2325464b20e88cec71b1605848839bf546
2 files changed