Prep to publish v0.22.1+5 (#77)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 50607cc..6969548 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,9 +1,10 @@
 ## 0.22.1+5
 
-Fix generic type error that occurs when using ChangeNotifier with a subclass of ChangeRecord.
-Previously, calling `notifyChanges()` on `class Foo with ChangeNotifier<CustomChangeRecord> {}`
-would throw a type error. Now, the `changes` stream emits a custom `ChangeRecords` class that
-implements the `List` interface. This change is backwards compatible.
+Fix generic type error that occurs when using ChangeNotifier with a subclass of
+ChangeRecord. Previously, calling `notifyChanges()` on
+`class Foo with ChangeNotifier<CustomChangeRecord> {}` would throw a type error.
+Now, the `changes` stream emits a custom `ChangeRecords` class that implements
+the `List` interface. This change is backwards compatible.
 
 ## 0.22.1+4
 
diff --git a/pubspec.yaml b/pubspec.yaml
index 3a2e7b0..2bd5882 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: observable
-version: 0.22.1+4
+version: 0.22.1+5
 author: Dart Team <misc@dartlang.org>
 description: Support for marking objects as observable
 homepage: https://github.com/dart-lang/observable
@@ -11,8 +11,8 @@
   meta: ^1.0.4
   quiver: '>=0.24.0 <3.0.0'
 dev_dependencies:
-  build_runner: '>=0.8.0 <0.10.0'
+  build_runner: '>=0.8.0 <2.0.0'
   build_test: ^0.10.0
-  build_web_compilers: '>=0.3.1 <0.5.0'
+  build_web_compilers: '>=0.3.1 <2.0.0'
   dart_style: ^1.0.9
   test: ^1.3.0