prep to publish 22.4.0 (#1023)

Author: devoncarew

protoc_plugin/CHANGELOG.md

@@ -1,13 +1,19 @@
-## 22.4.0-wip
+## 22.4.0
 
 * Update how we calculate import prefixes ([#1010]); import prefixes are now
   unique per-library instead of being unique across all generated libraries.
-* Ignore `unused_import` diagnostics for `*.pbjson.dart` files.
+* Ignore `unused_import` diagnostics for `*.pbjson.dart` files. ([#1013])
 * Revert the change to not generate empty `*.pbenum.dart` files; these can be
-  exported from other enum files.
-* Improve the readablity of generated gRPC client files.
+  exported from other enum files. ([#1016])
+* Improve the readablity of generated gRPC client files. ([#1021])
+* Adjust the text of generated file headers ('This is a generated file...').
+  ([#1022])
 
 [#1010]: https://github.com/google/protobuf.dart/issues/1010
+[#1013]: https://github.com/google/protobuf.dart/pull/1013
+[#1016]: https://github.com/google/protobuf.dart/pull/1016
+[#1021]: https://github.com/google/protobuf.dart/pull/1021
+[#1022]: https://github.com/google/protobuf.dart/pull/1022
 
 ## 22.3.0
 

protoc_plugin/pubspec.yaml

@@ -1,5 +1,5 @@
 name: protoc_plugin
-version: 22.4.0-wip
+version: 22.4.0
 description: A protobuf protoc compiler plugin used to generate Dart code.
 repository: https://github.com/google/protobuf.dart/tree/master/protoc_plugin