leveldb: update upstream verison 1.17 -> 1.18

ports/leveldb/build.sh

 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # All these tests rely on mkdir() working, and currently
 # neither newlib or glibc has mkdir plumbed through to the
 # IRT.
 #autocompact_test
 #corruption_test
 #db_test
@@ skipping 13 matching lines @@
     filter_block_test \
     log_test \
     memenv_test \
     skiplist_test \
     version_edit_test \
     version_set_test \
     write_batch_test"
 
 BUILD_DIR=${SRC_DIR}
 
+
 BuildStep() {
   export TARGET_OS=NaCl
   export AR=${NACLAR}
   export CC=${NACLCC}
   export CXX=${NACLCXX}
   LogExecute make clean
   LogExecute make -j${OS_JOBS} OPT=""
   LogExecute make -j${OS_JOBS} OPT="" tests programs
 }
 
 InstallStep() {
   MakeDir ${DESTDIR_LIB}
   MakeDir ${DESTDIR_INCLUDE}
   LogExecute cp libleveldb.a ${DESTDIR_LIB}
   LogExecute cp -r include/leveldb ${DESTDIR_INCLUDE}
 }
 
 TestStep() {
   if [ "${NACL_ARCH}" = "pnacl" ]; then
     return
   fi
 
   for test_binary in $EXECUTABLES; do
     echo "***** Running $test_binary.sh"
     ./$test_binary.sh
   done
 }