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

runtime/vm/flags.h

Index: runtime/vm/flags.h
diff --git a/runtime/vm/flags.h b/runtime/vm/flags.h
index 00339d19b6426689c518521e5d50ec557faa1b95..778ed33fdaad19aa92d285de479248cb1dcb7b5e 100644
--- a/runtime/vm/flags.h
+++ b/runtime/vm/flags.h
@@ -1,11 +1,11 @@
-// 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.
 
 #ifndef VM_FLAGS_H_
 #define VM_FLAGS_H_
 
-#include "vm/assert.h"
+#include "platform/assert.h"
 #include "vm/globals.h"
 
 typedef const char* charp;