Add _android files for building DartVM on Android

runtime/vm/gdbjit_android.cc

Index: runtime/vm/gdbjit_android.cc
diff --git a/runtime/vm/gdbjit_linux.cc b/runtime/vm/gdbjit_android.cc
similarity index 96%
copy from runtime/vm/gdbjit_linux.cc
copy to runtime/vm/gdbjit_android.cc
index 9fac94ef5e20c8c3eaa79f80787454f3683d0cc9..0c869fc5dcbc8a38b422206943fffb1f42c9d6b1 100644
--- a/runtime/vm/gdbjit_linux.cc
+++ b/runtime/vm/gdbjit_android.cc
@@ -1,4 +1,4 @@
-// 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.
 
@@ -6,7 +6,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#include "vm/gdbjit_linux.h"
+#include "vm/gdbjit_android.h"
 
 extern "C" {
   typedef enum {