Update yield warnings.

pkg/compiler/lib/src/compiler.dart

Index: pkg/compiler/lib/src/compiler.dart
diff --git a/pkg/compiler/lib/src/compiler.dart b/pkg/compiler/lib/src/compiler.dart
index 173f421d514a20b58b987ece1ea54dc82980d738..a99134f8ba338f2b050ebcd486949a9b934f1a00 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -2395,6 +2395,22 @@ class _CompilerCoreTypes implements CoreTypes {
 
   @override
   InterfaceType get stringType =>  stringClass.computeType(compiler);
+
+  @override
+  InterfaceType iterableType([DartType elementType = const DynamicType()]) {
+    return iterableClass.computeType(compiler)
+        .createInstantiation([elementType]);
+  }
+
+  @override
+  InterfaceType futureType([DartType elementType = const DynamicType()]) {
+    return futureClass.computeType(compiler).createInstantiation([elementType]);
+  }
+
+  @override
+  InterfaceType streamType([DartType elementType = const DynamicType()]) {
+    return streamClass.computeType(compiler).createInstantiation([elementType]);
+  }
 }
 
 typedef void InternalErrorFunction(Spannable location, String message);