Exception when opening encrypted box after re-initialising Hive

**Steps to Reproduce**
I updated Hive from version `2.0.0` -> `2.0.4`, I performed logic which re-initialises Hive (using `Hive.initFlutter`) with a new `subDir`, I then got the following exception when attempting to open an encrypted box:
```
7.3.0 - [Firebase/Firestore][I-FST000001] WatchStream (2839f3918) Stream error: 'Not found: Target id not found: 64'
flutter: Recovering corrupted box.
[VERBOSE-2:ui_dart_state.cc(186)] Unhandled Exception: HiveError: This should not happen. Please open an issue on GitHub.
#0 BinaryReaderImpl.readFrame (package:hive/src/binary/binary_reader_impl.dart:250:7)
#1 FrameHelper.framesFromBytes (package:hive/src/binary/frame_helper.dart:21:26)
#2 FrameIoHelper.framesFromFile (package:hive/src/io/frame_io_helper.dart:42:12)

#3 StorageBackendVm.initialize (package:hive/src/backend/vm/storage_backend_vm.dart:86:11)

#4 HiveImpl._openBox (package:hive/src/hive_impl.dart:116:9)

#5 HiveImpl.openBox (package:hive/src/hive_impl.dart:145:12)

#6 loadSearchResultsFromStorage. (package:hunni/middleware/file_middleware.dart:157:30)

```

Now whenever I open my app, when attempting to open an encrypted box I get the following exception:
```
[VERBOSE-2:ui_dart_state.cc(186)] Unhandled Exception: HiveError: This should not happen. Please open an issue on GitHub.
#0 BinaryReaderImpl.readFrame (package:hive/src/binary/binary_reader_impl.dart:250:7)
#1 FrameHelper.framesFromBytes (package:hive/src/binary/frame_helper.dart:21:26)
#2 FrameIoHelper.framesFromFile (package:hive/src/io/frame_io_helper.dart:42:12)

#3 StorageBackendVm.initialize (package:hive/src/backend/vm/storage_backend_vm.dart:86:11)

#4 HiveImpl._openBox (package:hive/src/hive_impl.dart:116:9)

#5 HiveImpl.openBox (package:hive/src/hive_impl.dart:145:12)

```

**Code sample**
```
Provide a few simple lines of code to show your problem.
```

**Version**
- Platform: iOS
- Flutter version: `2.0.3`
- Hive version: `2.0.4`