引入extended_image到主项目中，报错

[yfm-pliny]

flutter版本 1.9.1+hotfix.6 ，是我用到方式不对吗？
报错日志：
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_memory_image_provider.dart:19:48: Error: 'DecoderCallback' isn't a type.
Future<ui.Codec> _loadAsync(MemoryImage key, DecoderCallback decode) {
^^^^^^^^^^^^^^^
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_file_image_provider.dart:13:44: Error: 'DecoderCallback' isn't a type.
ImageStreamCompleter load(FileImage key, DecoderCallback decode) {
^^^^^^^^^^^^^^^
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_file_image_provider.dart:23:46: Error: 'DecoderCallback' isn't a type.
Future<ui.Codec> _loadAsync(FileImage key, DecoderCallback decode) async {
^^^^^^^^^^^^^^^
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_asset_bundle_image_provider.dart:35:54: Error: 'DecoderCallback' isn't a type.
ImageStreamCompleter load(AssetBundleImageKey key, DecoderCallback decode) {
^^^^^^^^^^^^^^^
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_asset_bundle_image_provider.dart:52:32: Error: 'DecoderCallback' isn't a type.
AssetBundleImageKey key, DecoderCallback decode) async {
^^^^^^^^^^^^^^^
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_asset_bundle_image_provider.dart:88:54: Error: 'DecoderCallback' isn't a type.
ImageStreamCompleter load(AssetBundleImageKey key, DecoderCallback decode) {
^^^^^^^^^^^^^^^
/Applications/flutter/.pub-cache/hosted/pub.flutter-io.cn/extended_image_library-0.1.9/lib/src/extended_asset_bundle_image_provider.dart:105:32: Error: 'DecoderCallback' isn't a type.
AssetBundleImageKey key, DecoderCallback decode) async {
^^^^^^^^^^^^^^^

[zmtzawqlp]

double check #89