Dart 3 compatibility: some classes are used as mixins

[Oleh Prypin]

These 3 classes should be changed to mixin, otherwise the usages marked below them are an error with Dart language version 3.0

• CancellableMixin

  http2/lib/src/error_handler.dart

  Line 43 in 7518027

   class CancellableMixin { 

  • http2/lib/src/flowcontrol/stream_queues.dart

    Line 157 in 7518027

     with TerminatableMixin, ClosableMixin, CancellableMixin { 

• ClosableMixin

  http2/lib/src/error_handler.dart

  Line 61 in 7518027

   class ClosableMixin { 

  • http2/lib/src/flowcontrol/connection_queues.dart

    Line 179 in 7518027

     with TerminatableMixin, ClosableMixin { 

  • http2/lib/src/flowcontrol/connection_queues.dart

    Line 35 in 7518027

     with TerminatableMixin, ClosableMixin { 

  • http2/lib/src/flowcontrol/stream_queues.dart

    Line 157 in 7518027

     with TerminatableMixin, ClosableMixin, CancellableMixin { 

  • http2/lib/src/flowcontrol/stream_queues.dart

    Line 23 in 7518027

     with TerminatableMixin, ClosableMixin { 

  • http2/lib/src/streams/stream_handler.dart

    Line 131 in 7518027

     class StreamHandler extends Object with TerminatableMixin, ClosableMixin { 

• TerminatableMixin

  http2/lib/src/error_handler.dart

  Line 10 in 7518027

   class TerminatableMixin { 

  • http2/lib/src/flowcontrol/connection_queues.dart

    Line 179 in 7518027

     with TerminatableMixin, ClosableMixin { 

  • http2/lib/src/flowcontrol/connection_queues.dart

    Line 35 in 7518027

     with TerminatableMixin, ClosableMixin { 

  • http2/lib/src/flowcontrol/stream_queues.dart

    Line 157 in 7518027

     with TerminatableMixin, ClosableMixin, CancellableMixin { 

  • http2/lib/src/flowcontrol/stream_queues.dart

    Line 23 in 7518027

     with TerminatableMixin, ClosableMixin { 

  • http2/lib/src/ping/ping_handler.dart

    Line 16 in 7518027

     class PingHandler extends Object with TerminatableMixin { 

  • http2/lib/src/settings/settings.dart

    Line 88 in 7518027

     class SettingsHandler extends Object with TerminatableMixin { 

  • http2/lib/src/streams/stream_handler.dart

    Line 131 in 7518027

     class StreamHandler extends Object with TerminatableMixin, ClosableMixin {