Ceph

The ASSERT_DEATH test in unittest_pglog (at the very end of merge_log test) seems to cause transient test failure due to timeout. We already removed the EXPECT_DEATH tests in http://tracker.ceph.com/issues/18030 so I'm guessing the solution in this case is similar (remove the test).

----------------------------------------------------------
[==========] Running 42 tests from 4 test cases.
[----------] Global test environment set-up.
[----------] 23 tests from PGLogTest
[ RUN      ] PGLogTest.rewind_divergent_log
[       OK ] PGLogTest.rewind_divergent_log (1 ms)
[ RUN      ] PGLogTest.merge_old_entry
[       OK ] PGLogTest.merge_old_entry (0 ms)
[ RUN      ] PGLogTest.merge_log

[WARNING] /opt/j/ws/mkck/src/googletest/googletest/src/gtest-death-test.cc:836:: Death tests use fork(), which is unsafe particularly in a threaded context. For this test, Google Test detected 3 threads.