Adds support for mojo apps to live in their own directory

mojo/shell/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.
 
 import("//third_party/mojo/src/mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 
 source_set("shell") {
   output_name = "mojo_shell"
   sources = [
@@ skipping 25 matching lines @@
     "//third_party/mojo/src/mojo/public/interfaces/application:application",
     "//mojo/services/network/public/interfaces",
     "//url",
   ]
   deps = [
     "//base/third_party/dynamic_annotations",
     "//crypto:crypto",
     "//url",
     "//third_party/mojo/src/mojo/edk/system",
     "//mojo/environment:chromium",
+    "//mojo/util:filename_util",
     "//third_party/mojo_services/src/content_handler/public/interfaces",
     "//mojo/runner:native_application_support",
   ]
 }
 
 test("tests") {
   output_name = "mojo_shell_unittests"
 
   sources = [
     "application_manager_unittest.cc",
@@ skipping 13 matching lines @@
     "//testing/gtest",
     "//url",
   ]
 }
 
 mojom("test_bindings") {
   sources = [
     "test.mojom",
   ]
 }