Move assert.h/assert.cc from runtime/vm to runtime/platform

runtime/bin/file_win.cc

Index: runtime/bin/file_win.cc
diff --git a/runtime/bin/file_win.cc b/runtime/bin/file_win.cc
index 6d0522145d3c327f9267dc73188652b8c3781d05..6ddd54a276e20635ca21600128e7ef9198c3774c 100644
--- a/runtime/bin/file_win.cc
+++ b/runtime/bin/file_win.cc
@@ -1,7 +1,9 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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 "bin/file.h"
+
 #include <fcntl.h>
 #include <io.h>
 #include <stdio.h>
@@ -9,7 +11,6 @@
 #include <sys/stat.h>
 
 #include "bin/builtin.h"
-#include "bin/file.h"
 
 class FileHandle {
  public: