dart2js: add function type to the model.

pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart

Index: pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart
diff --git a/pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart b/pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart
index d6272700206cab5d3a90d3da3aff06ba682a3717..6ccad185c4359478d8896872ea2125c8dabd2ece 100644
--- a/pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.dart
@@ -629,15 +629,6 @@ function parseFunctionDescriptor(proto, name, descriptor) {
 }
 """;
 
-  js.Expression _generateFunctionType(DartType memberType) {
-    if (memberType.containsTypeVariables) {
-      js.Expression thisAccess = js.js(r'this.$receiver');
-      return backend.rti.getSignatureEncoding(memberType, thisAccess);
-    } else {
-      return js.number(backend.emitter.metadataCollector.reifyType(memberType));
-    }
-  }
-
   js.Expression _encodeOptionalParameterDefaultValues(DartMethod method) {
     js.Expression result;
     // TODO(herhut): Replace [js.LiteralNull] with [js.ArrayHole].
@@ -686,7 +677,7 @@ function parseFunctionDescriptor(proto, name, descriptor) {
           bool isIntercepted = backend.isInterceptedMethod(method.element);
           data.add(new js.LiteralBool(isIntercepted));
           data.add(js.string(method.tearOffName));
-          data.add(_generateFunctionType(method.type));
+          data.add((method.functionType));
         }
 
         data.addAll(method.parameterStubs.expand(makeNameCallNameCodeTriplet));
@@ -735,7 +726,7 @@ function parseFunctionDescriptor(proto, name, descriptor) {
         var data = [unparse(compiler, method.code)];
         data.add(js.string(method.callName));
         data.add(js.string(method.tearOffName));
-        data.add(_generateFunctionType(method.type));
+        data.add(method.functionType);
         data.addAll(method.parameterStubs.expand(makeNameCallNameCodeTriplet));
         if (method.canBeApplied) {
           data.add(js.number(method.requiredParameterCount));