Dart: Updates Dart VM revision.

mojo/dart/embedder/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 action("generate_snapshot_bin") {
   deps = [
     "//dart/runtime/bin:gen_snapshot",
   ]
   inputs = [
     "snapshot.dart",
@@ skipping 20 matching lines @@
   outputs = [
     output,
   ]
 
   script = "//dart/runtime/tools/create_snapshot_bin.py"
   builtin_path = rebase_path("//mojo/dart/embedder/builtin.dart")
   bindings_path = rebase_path("//mojo/public/dart/bindings.dart")
   core_path = rebase_path("//mojo/public/dart/core.dart")
   args = [
     "--executable", rebase_path("$root_out_dir/gen_snapshot"),
+    "--package_root", rebase_path("$root_gen_dir"),
     "--script", rebase_path("snapshot.dart"),
     "--output_bin", rebase_path(output, root_build_dir),
     "--target_os", os,
     "--url_mapping=dart:mojo_bindings,$bindings_path",
     "--url_mapping=dart:mojo_builtin,$builtin_path",
     "--url_mapping=dart:mojo_core,$core_path",
   ]
 }
 
 action("generate_snapshot_file") {
@@ skipping 44 matching lines @@
 
   defines = []
   if (is_debug) {
     defines += [ "DEBUG" ]
   } else {
     defines += [ "NDEBUG" ]
   }
 
   include_dirs = [ "//dart/runtime" ]
 }