Fix travis java_test

Summary:
Travis java_test is failing because `make clean` happens after `build_version.cc` is generated. Fixing it.

Closes #2299
Closes https://github.com/facebook/rocksdb/pull/2307

Differential Revision: D5070781

Pulled By: yiwu-arbug

fbshipit-source-id: 18d3ea11d602048f4786b8c7a41f49c2aee774cd

.travis.yml

@@ -60,7 +60,7 @@ script:
   - if [[ "${TEST_GROUP}" == 'platform_dependent3' ]]; then OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=checkpoint_test ROCKSDBTESTS_END=db_block_cache_test make -j4 check_some; fi
   - if [[ "${TEST_GROUP}" == '1' ]]; then OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=db_block_cache_test ROCKSDBTESTS_END=comparator_db_test make -j4 check_some; fi
   - if [[ "${TEST_GROUP}" == '2' ]]; then OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=comparator_db_test make -j4 check_some; fi
-  - if [[ "${JOB_NAME}" == 'java_test' ]]; then OPT=-DTRAVIS V=1 make clean jclean rocksdbjava jtest; fi
+  - if [[ "${JOB_NAME}" == 'java_test' ]]; then OPT=-DTRAVIS V=1 make clean jclean && make rocksdbjava jtest; fi
   - if [[ "${JOB_NAME}" == 'lite_build' ]]; then OPT="-DTRAVIS -DROCKSDB_LITE" V=1 make -j4 static_lib; fi
   - if [[ "${JOB_NAME}" == 'examples' ]]; then OPT=-DTRAVIS V=1 make -j4 static_lib; cd examples; make -j4; fi
   - if [[ "${JOB_NAME}" == 'cmake' ]]; then mkdir build && cd build && cmake .. && make -j4 rocksdb; fi