Dart: bump mojo_sdk version

TBR

Review URL: https://codereview.chromium.org/1658723008 .
diff --git a/mojo/dart/packages/mojo_sdk/CHANGELOG.md b/mojo/dart/packages/mojo_sdk/CHANGELOG.md
index 3e83f44..68b750f 100644
--- a/mojo/dart/packages/mojo_sdk/CHANGELOG.md
+++ b/mojo/dart/packages/mojo_sdk/CHANGELOG.md
@@ -1,3 +1,9 @@
+## 0.2.13
+
+  - 25 changes: https://github.com/domokit/mojo/compare/fa66287...ecb64e7
+
+  MOJO_SDK: ecb64e7a16dca8374350e5b329694de85a7a1476
+
 ## 0.2.12
 
   - 37 changes: https://github.com/domokit/mojo/compare/47b52f1...147dc02
diff --git a/mojo/dart/packages/mojo_sdk/pubspec.yaml b/mojo/dart/packages/mojo_sdk/pubspec.yaml
index 90b6690..53b573c 100644
--- a/mojo/dart/packages/mojo_sdk/pubspec.yaml
+++ b/mojo/dart/packages/mojo_sdk/pubspec.yaml
@@ -1,10 +1,10 @@
 author: Chromium Authors <mojo-dev@googlegroups.com>
 dependencies:
-  mojo: 0.4.12
-  mojo_apptest: 0.2.16
-  mojo_services: 0.4.15
-  mojom: 0.2.16
+  mojo: 0.4.13
+  mojo_apptest: 0.2.17
+  mojo_services: 0.4.16
+  mojom: 0.2.17
 description: A meta package for the Dart Mojo SDK
 homepage: https://github.com/domokit/mojo
 name: mojo_sdk
-version: 0.2.12
+version: 0.2.13