dart2js: support tear-offs in the startup emitter.

sdk/lib/_internal/js_runtime/lib/core_patch.dart

Index: sdk/lib/_internal/js_runtime/lib/core_patch.dart
diff --git a/sdk/lib/_internal/js_runtime/lib/core_patch.dart b/sdk/lib/_internal/js_runtime/lib/core_patch.dart
index 2ec85f03b6bbffea3d8ebc38c123b5d06f8d7782..22186f69c49787786e367ae9f68195c1d74dad25 100644
--- a/sdk/lib/_internal/js_runtime/lib/core_patch.dart
+++ b/sdk/lib/_internal/js_runtime/lib/core_patch.dart
@@ -8,6 +8,7 @@ import 'dart:_interceptors';
 import 'dart:_js_helper' show patch,
                               patch_full,
                               patch_lazy,
+                              patch_startup,
                               checkInt,
                               getRuntimeType,
                               jsonEncodeNative,
@@ -77,6 +78,14 @@ class Function {
         namedArguments == null ? null : _symbolMapToStringMap(namedArguments));
   }
 
+  @patch_startup
+  static apply(Function function,
+               List positionalArguments,
+               [Map<Symbol, dynamic> namedArguments]) {
+    return Primitives.applyFunctionNewEmitter(function, positionalArguments,
+        namedArguments == null ? null : _symbolMapToStringMap(namedArguments));
+  }
+
   static Map<String, dynamic> _toMangledNames(
       Map<Symbol, dynamic> namedArguments) {
     Map<String, dynamic> result = {};