fcb206b667
Summary: Allow users to give a callback function with parameter using sync point, so more complicated verification can be done in tests. Use it in DBTest.DynamicLevelCompressionPerLevel2 so that failures will be more easy to debug. Test Plan: Run all tests. Run DBTest.DynamicLevelCompressionPerLevel2 with valgrind check. Reviewers: rven, yhchiang, anthony, kradhakrishnan, igor Reviewed By: igor Subscribers: leveldb, dhruba Differential Revision: https://reviews.facebook.net/D36999