a180c5cc3a
Summary: db_stress does not yet cover is GetMergeOperands(), added GetMergeOperands() to db_stress. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9804 Test Plan: ```make -j32 db_stress``` ```python3 tools/db_crashtest.py blackbox --simple --interval=30 --duration=2400 --max_key=100000 --write_buffer_size=524288 --target_file_size_base=524288 --max_bytes_for_level_base=2097152 --value_size_mult=33``` Reviewed By: ajkr Differential Revision: D35387137 Pulled By: cbi42 fbshipit-source-id: 8f851ef68b5af4d824128ad55ebe564f7ad6f7e6