Implement @patch annotation for patch class members

runtime/lib/function_patch.dart

Index: runtime/lib/function_patch.dart
diff --git a/runtime/lib/function_patch.dart b/runtime/lib/function_patch.dart
index 7ed74c855a6838e65a4894408b8b52f4c2b87f3f..5acd4f979524edd7bf6c0d828e376cc9f832c105 100644
--- a/runtime/lib/function_patch.dart
+++ b/runtime/lib/function_patch.dart
@@ -6,9 +6,9 @@
   static _apply(List arguments, List names)
       native "Function_apply";
 
-  /* @patch */ static apply(Function function,
-                            List positionalArguments,
-                            [Map<Symbol, dynamic> namedArguments]) {
+  @patch static apply(Function function,
+                      List positionalArguments,
+                      [Map<Symbol, dynamic> namedArguments]) {
     int numPositionalArguments = 1 +  // Function is first implicit argument.
         (positionalArguments != null ? positionalArguments.length : 0);
     int numNamedArguments = namedArguments != null ? namedArguments.length : 0;