Fix asan_check failures

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5589

Test Plan: TEST_TMPDIR=/dev/shm/rocksdb COMPILE_WITH_ASAN=1 OPT=-g make J=64 -j64 asan_check

Differential Revision: D16361081

Pulled By: anand1976

fbshipit-source-id: 09474832b9cfb318a840d4b633e22dfad105d58c

db/import_column_family_test.cc

@@ -298,6 +298,7 @@ TEST_F(ImportColumnFamilyTest, ImportExportedSSTFromAnotherCF) {
   ASSERT_OK(checkpoint->ExportColumnFamily(handles_[1], export_files_dir_,
                                            &metadata_ptr_));
   ASSERT_NE(metadata_ptr_, nullptr);
+  delete checkpoint;
 
   ImportColumnFamilyOptions import_options;
   import_options.move_files = false;
@@ -407,6 +408,7 @@ TEST_F(ImportColumnFamilyTest, ImportExportedSSTFromAnotherDB) {
   ASSERT_OK(checkpoint->ExportColumnFamily(handles_[1], export_files_dir_,
                                            &metadata_ptr_));
   ASSERT_NE(metadata_ptr_, nullptr);
+  delete checkpoint;
 
   // Create a new db and import the files.
   DB* db_copy;
@@ -424,6 +426,7 @@ TEST_F(ImportColumnFamilyTest, ImportExportedSSTFromAnotherDB) {
     ASSERT_EQ(Get(1, Key(i)), value);
   }
   db_copy->DropColumnFamily(cfh);
+  db_copy->DestroyColumnFamilyHandle(cfh);
   test::DestroyDir(env_, dbname_ + "/db_copy");
 }