Service isolate requests Observatory assets from embedder

runtime/bin/observatory_assets_empty.cc

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2015, 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.
 
-// This file is linked into the dart executable when it does not have a
-// snapshot linked into it.
+// This file is linked into the dart executable when it does not have
+// Observatory baked in.
 
 #if defined(_WIN32)
 typedef unsigned __int8 uint8_t;
 #else
 #include <inttypes.h>
 #include <stdint.h>
 #endif
 #include <stddef.h>
 
-
 namespace dart {
 namespace bin {
 
-const uint8_t* vm_isolate_snapshot_buffer = NULL;
-const uint8_t* isolate_snapshot_buffer = NULL;
+static const char observatory_assets_archive_[] = { '\0' };
+unsigned int observatory_assets_archive_len = 0;
+const char* observatory_assets_archive = observatory_assets_archive_;
 
 }  // namespace bin
 }  // namespace dart