Prepare cherry-pick release - DevTools 2.28.4

packages/devtools_app/lib/devtools.dart

diff --git a/packages/devtools_app/lib/devtools.dart b/packages/devtools_app/lib/devtools.dart
index 72f9f8a..8dfd269 100644
--- a/packages/devtools_app/lib/devtools.dart
+++ b/packages/devtools_app/lib/devtools.dart
@@ -9,4 +9,4 @@
 // the constant declaration `const String version =`.
 // If you change the declaration you must also modify the regex in
 // tools/update_version.dart.
-const String version = '2.28.3';
+const String version = '2.28.4';

packages/devtools_app/pubspec.yaml

diff --git a/packages/devtools_app/pubspec.yaml b/packages/devtools_app/pubspec.yaml
index 21a8665..3e846a0 100644
--- a/packages/devtools_app/pubspec.yaml
+++ b/packages/devtools_app/pubspec.yaml
@@ -4,7 +4,7 @@
 
 # Note: this version should only be updated by running tools/update_version.dart
 # that updates all versions of devtools packages (devtools_app, devtools_test).
-version: 2.28.3
+version: 2.28.4
 
 repository: https://github.com/flutter/devtools/tree/master/packages/devtools_app
 
@@ -67,14 +67,14 @@
   vm_service: ^11.10.0
   # TODO https://github.com/dart-lang/sdk/issues/52853 - unpin this version
   vm_snapshot_analysis: 0.7.2
-  web: ^0.2.1-beta
+  web: 0.3.0
   web_socket_channel: ^2.1.0
   # widget_icons: ^0.0.1
 
 dev_dependencies:
   args: ^2.4.2
   build_runner: ^2.3.3
-  devtools_test: 2.28.3
+  devtools_test: 2.28.4
   fake_async: ^1.3.1
   flutter_driver:
     sdk: flutter

packages/devtools_test/pubspec.yaml

diff --git a/packages/devtools_test/pubspec.yaml b/packages/devtools_test/pubspec.yaml
index ec0b475..1ef05eb 100644
--- a/packages/devtools_test/pubspec.yaml
+++ b/packages/devtools_test/pubspec.yaml
@@ -7,7 +7,7 @@
 # When publishing new versions of this package be sure to publish a new version
 # of package:devtools as well. package:devtools contains a compiled snapshot of
 # this package.
-version: 2.28.3
+version: 2.28.4
 
 repository: https://github.com/flutter/devtools/tree/master/packages/devtools_test
 
@@ -19,7 +19,7 @@
   async: ^2.0.0
   collection: ^1.15.0
   devtools_shared: ^4.0.1
-  devtools_app: 2.28.3
+  devtools_app: 2.28.4
   devtools_app_shared:
     path: ../devtools_app_shared
   flutter: