instantiate generic tear-offs, fixes #525

tool/input_sdk/private/ddc_runtime/classes.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 operations that define and manipulate Dart
 /// classes.  Included in this are:
 ///   - Generics
 ///   - Class metadata
 ///   - Extension methods
 ///
@@ skipping 152 matching lines @@
   if ($f === void 0) $f = $obj[$name];
   $f = $f.bind($obj);
   // TODO(jmesserly): track the function's signature on the function, instead
   // of having to go back to the class?
   let sig = $getMethodType($obj, $name);
   $assert_(sig);
   $tag($f, sig);
   return $f;
 })()''');
 
+/// Instantiate a generic method.
+///
+/// We need to apply the type arguments both to the function, as well as its
+/// associated function type.
+gbind(f, @rest typeArgs) {
+  var result = JS('', '#(...#)', f, typeArgs);
+  var sig = JS('', '#(...#)', _getRuntimeType(f), typeArgs);
+  tag(result, sig);
+  return result;
+}
+
 // Set up the method signature field on the constructor
 _setMethodSignature(f, sigF) => JS('', '''(() => {
   $defineMemoizedGetter($f, $_methodSig, () => {
     let sigObj = $sigF();
     sigObj.__proto__ = $f.__proto__[$_methodSig];
     return sigObj;
   });
 })()''');
 
 // Set up the constructor signature field on the constructor
@@ skipping 167 matching lines @@
 })()''');
 
 /// Sets the element type of a list literal.
 list(obj, elementType) =>
     JS('', '$setType($obj, ${getGenericClass(JSArray)}($elementType))');
 
 setBaseClass(derived, base) => JS('', '''(() => {
   // Link the extension to the type it's extending as a base class.
   $derived.prototype.__proto__ = $base.prototype;
 })()''');