Add mips skeleton sources.

runtime/vm/disassembler_mips.cc

Index: runtime/vm/disassembler_mips.cc
===================================================================
--- runtime/vm/disassembler_mips.cc	(revision 0)
+++ runtime/vm/disassembler_mips.cc	(revision 0)
@@ -0,0 +1,30 @@
+// Copyright (c) 2013, 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 "vm/disassembler.h"
+
+#include "vm/globals.h"  // Needed here to get TARGET_ARCH_MIPS.
+#if defined(TARGET_ARCH_MIPS)
+#include "platform/assert.h"
+
+namespace dart {
+
+int Disassembler::DecodeInstruction(char* hex_buffer, intptr_t hex_size,
+                                    char* human_buffer, intptr_t human_size,
+                                    uword pc) {
+  UNIMPLEMENTED();
+  return 0;
+}
+
+
+void Disassembler::Disassemble(uword start,
+                               uword end,
+                               DisassemblyFormatter* formatter,
+                               const Code::Comments& comments) {
+  UNIMPLEMENTED();
+}
+
+}  // namespace dart
+
+#endif  // defined TARGET_ARCH_MIPS