Breaking changes in 'analyzer' package.

pkg/analyzer/lib/src/string_source.dart

Index: pkg/analyzer/lib/src/string_source.dart
diff --git a/pkg/analyzer/lib/src/string_source.dart b/pkg/analyzer/lib/src/string_source.dart
index 24d55c1fb31f389d56f7b632abc6201f70d7df78..bfeedf091452c6a80c2ff12517b31823d868bd97 100644
--- a/pkg/analyzer/lib/src/string_source.dart
+++ b/pkg/analyzer/lib/src/string_source.dart
@@ -40,6 +40,10 @@ class StringSource implements Source {
 
   bool get isInSystemLibrary => false;
 
-  Source resolveRelative(Uri relativeUri) => throw new UnsupportedError(
+  @override
+  Uri get uri => throw new UnsupportedError(
+      "StringSource doesn't support uri.");
+
+  Uri resolveRelativeUri(Uri relativeUri) => throw new UnsupportedError(
       "StringSource doesn't support resolveRelative.");
 }