Improve the performance of closure-converted code.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index c1cec8022088ff8267b686a9239c247baac77a38..36ca4d6c650f26c3517b31374343341eb34bce04 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -5625,6 +5625,9 @@ const char* Function::KindToCString(RawFunction::Kind kind) {
     case RawFunction::kImplicitClosureFunction:
       return "ImplicitClosureFunction";
       break;
+    case RawFunction::kConvertedClosureFunction:
+      return "ConvertedClosureFunction";
+      break;
     case RawFunction::kSignatureFunction:
       return "SignatureFunction";
       break;
@@ -6352,7 +6355,7 @@ RawFunction* Function::InstantiateSignatureFrom(
   if (IsConvertedClosureFunction()) {
     sig = Function::NewConvertedClosureFunction(
         String::Handle(zone, name()), parent, TokenPosition::kNoSource);
-    // TODO(sjindel): Kernel generic methods undone. Handle type parameters
+    // TODO(30455): Kernel generic methods undone. Handle type parameters
     // correctly when generic closures are supported. Until then, all type
     // parameters to this target are used for captured type variables, so they
     // aren't relevant to the type of the function.