Convert dart_utils.js to input_sdk/lib/_internal/utils.dart (#310)

lib/runtime/dart/_internal.js

Index: lib/runtime/dart/_internal.js
diff --git a/lib/runtime/dart/_internal.js b/lib/runtime/dart/_internal.js
index 7d8b6b504e45bd8356ad240d4ae0891c61bcffc9..5d0fb66387e36116a7d389bc0a0055229437ecb1 100644
--- a/lib/runtime/dart/_internal.js
+++ b/lib/runtime/dart/_internal.js
@@ -620,7 +620,7 @@ dart_library.library('dart/_internal', null, /* Imports */[
         super.IterableBase();
       }
       get iterator() {
-        return new (ExpandIterator$(S, T))(this[_iterable][dartx.iterator], dart.as(this[_f], __CastType0));
+        return new (ExpandIterator$(S, T))(this[_iterable][dartx.iterator], dart.as(this[_f], __CastType0$(S, T)));

[vsm, 2015/11/30 16:50:06]

Do you know what change triggered this?  The new version looks better, but we
probably ought to fix the Dart code to eliminate this cast.

[Jennifer Messerly, 2015/11/30 18:54:11]

Just a guess: I changed Analyzer to use FunctionElement instead of fake typedefs
for function typed parameters, and fixed its enclosingElement to correctly track
type parameters. It looks like the result is they're tracking generic
substitutions better. It wasn't my intent but it looks like maybe it fixed a
soundness issue.

       }
     }
     dart.setSignature(ExpandIterable, {
@@ -1317,7 +1317,7 @@ dart_library.library('dart/_internal', null, /* Imports */[
       }
       where(iterable, f) {
         dart.as(f, dart.functionType(core.bool, [dart.dynamic]));
-        return new (WhereIterable$(T))(dart.as(iterable, core.Iterable$(T)), dart.as(f, __CastType2));
+        return new (WhereIterable$(T))(dart.as(iterable, core.Iterable$(T)), dart.as(f, __CastType2$(T)));
       }
       static map(iterable, f) {
         dart.as(f, dart.functionType(dart.dynamic, [dart.dynamic]));