dart:mirrors workaround for generic methods

pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/types.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// This library defines the representation of runtime types.
 part of dart._runtime;
 
 final metadata = JS('', 'Symbol("metadata")');
 
 /// The symbol used to store the cached `Type` object associated with a class.
@@ skipping 494 matching lines @@
 functionType(returnType, args, extra) =>
     _functionType(false, returnType, args, extra);
 
 ///
 /// Create a definite function type. No substitution of dynamic for
 /// bottom occurs.
 ///
 definiteFunctionType(returnType, args, extra) =>
     _functionType(true, returnType, args, extra);
 
+///
+/// TODO(vsm): Remove when mirrors is deprecated.
+/// This is a temporary workaround to support dart:mirrors, which doesn't
+/// understand generic methods.
+///
+getFunctionTypeMirror(AbstractFunctionType type) {
+  if (type is GenericFunctionType) {
+    var typeArgs = new List.filled(type.formalCount, dynamic);
+    return type.instantiate(typeArgs);
+  }
+  return type;
+}
+
 bool isType(obj) => JS(
     '',
     '''(() => {
   return $_getRuntimeType($obj) === $Type;
   })()''');
 
 String typeName(type) => JS(
     '',
     '''(() => {
   if ($type === void 0) return "undefined type";
@@ skipping 387 matching lines @@
     return true;
   }
 
   let typeArgs = $getGenericArgs($type);
   if (!typeArgs) return true;
   for (let t of typeArgs) {
     if (t != $Object && t != $dynamic) return false;
   }
   return true;
 })()''');