Fix lifetime of leveldb::MojoEnv instances.

components/leveldb/leveldb_service_impl.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_LEVELDB_LEVELDB_SERVICE_IMPL_H_
 #define COMPONENTS_LEVELDB_LEVELDB_SERVICE_IMPL_H_
 
 #include "base/memory/ref_counted.h"
 #include "components/leveldb/leveldb_mojo_proxy.h"
 #include "components/leveldb/public/interfaces/leveldb.mojom.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 
 namespace leveldb {
 
+class MojoEnv;
+
 // Creates LevelDBDatabases based scoped to a |directory|/|dbname|.
 class LevelDBServiceImpl : public mojom::LevelDBService {
  public:
   // The |file_task_runner| is used to run tasks to interact with the
   // file_service. Specifically this task runner must NOT be the same as the
   // task runner this implementation runs on, or deadlock might occur.
-  LevelDBServiceImpl(
-      scoped_refptr<base::SingleThreadTaskRunner> file_task_runner);
+  explicit LevelDBServiceImpl(MojoEnv* env);
   ~LevelDBServiceImpl() override;
 
   // Overridden from LevelDBService:
-  void SetEnvironmentName(const std::string& name) override;
   void Open(filesystem::mojom::DirectoryPtr directory,
             const std::string& dbname,
             leveldb::mojom::LevelDBDatabaseAssociatedRequest database,
             const OpenCallback& callback) override;
   void OpenWithOptions(
       leveldb::mojom::OpenOptionsPtr open_options,
       filesystem::mojom::DirectoryPtr directory,
       const std::string& dbname,
       leveldb::mojom::LevelDBDatabaseAssociatedRequest database,
       const OpenCallback& callback) override;
   void OpenInMemory(leveldb::mojom::LevelDBDatabaseAssociatedRequest database,
                     const OpenInMemoryCallback& callback) override;
   void Destroy(filesystem::mojom::DirectoryPtr directory,
                const std::string& dbname,
                const DestroyCallback& callback) override;
 
  private:
-  // Thread to own the mojo message pipe. Because leveldb spawns multiple
-  // threads that want to call file stuff, we create a dedicated thread to send
-  // and receive mojo message calls.
-  scoped_refptr<LevelDBMojoProxy> thread_;
-
-  std::string environment_name_;
+  MojoEnv* env_;
 
   DISALLOW_COPY_AND_ASSIGN(LevelDBServiceImpl);
 };
 
 }  // namespace leveldb
 
 #endif  // COMPONENTS_LEVELDB_LEVELDB_SERVICE_IMPL_H_