Support using a mock SDK with the resolver in code-transformers, and switch

pkg/polymer/pubspec.yaml

Index: pkg/polymer/pubspec.yaml
diff --git a/pkg/polymer/pubspec.yaml b/pkg/polymer/pubspec.yaml
index a2e7825c09362127b27fbb368a5cee4292e69cb4..bb723d54cc2b85c0c1b0eb06169f36e9a9ff473c 100644
--- a/pkg/polymer/pubspec.yaml
+++ b/pkg/polymer/pubspec.yaml
@@ -11,7 +11,7 @@ dependencies:
   args: '>=0.10.0 <0.12.0'
   barback: '>=0.9.0 <0.15.0'
   browser: '>=0.10.0 <0.11.0'
-  code_transformers: '>=0.1.0 <0.2.0'
+  code_transformers: '>=0.2.0 <0.2.0'
   html5lib: '>=0.11.0 <0.12.0'
   logging: '>=0.9.0 <0.10.0'
   observe: '>=0.10.0 <0.11.0'