Fix the build on 64-bit.

runtime/lib/mirrors.cc

 // Copyright (c) 2012, 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.
 
 #include "include/dart_api.h"
 #include "include/dart_debugger_api.h"
 #include "include/dart_mirrors_api.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"  // TODO(11742): Remove with CreateMirrorRef.
 #include "vm/bootstrap_natives.h"
@@ skipping 1458 matching lines @@
   // TODO(11771): This won't find private members.
   const Function& function = Function::Handle(
         Resolver::ResolveStatic(klass,
                                 function_name,
                                 number_of_arguments,
                                 Object::empty_array(),
                                 Resolver::kIsQualified));
   if (function.IsNull()) {
     const String& klass_name = String::Handle(klass.Name());
     const String& message = String::Handle(
-      String::NewFormatted("%s: did not find %d-arg static method '%s.%s'.",
+      String::NewFormatted("%s: did not find static method '%s.%s'.",

[regis, 2013/07/15 22:34:26]

FYI, instead of "find  %d-arg", you would write "find %"Pd"-arg". 

                            "ClassMirror_invoke",
-                           number_of_arguments,
                            klass_name.ToCString(),
                            function_name.ToCString()));
     ThrowMirroredCompilationError(message);
     UNREACHABLE();
   }
   Object& result = Object::Handle(DartEntry::InvokeFunction(function,
                                                             positional_args));
   if (result.IsError()) {
     ThrowInvokeError(Error::Cast(result));
     UNREACHABLE();
@@ skipping 327 matching lines @@
 
 DEFINE_NATIVE_ENTRY(MethodMirror_name, 1) {
   const MirrorReference& func_ref =
       MirrorReference::CheckedHandle(arguments->NativeArgAt(0));
   Function& func = Function::Handle();
   func ^= func_ref.referent();
   return func.UserVisibleName();
 }
 
 }  // namespace dart