Back button should be able to close apps

sky/shell/BUILD.gn

 # Copyright 2015 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.
 
 common_deps = [
   "//base",
   "//base:i18n",
   "//build/config/sanitizers:deps",
   "//dart/runtime:libdart",
   "//mojo/common",
@@ skipping 101 matching lines @@
     deps = [
       "//base:base_java",
       "//mojo/android:system_java",
       "//mojo/public/interfaces/application:application_java",
       "//mojo/public/java:bindings",
       "//mojo/public/java:system",
       "//mojo/services/network/public/interfaces:interfaces_java",
       "//services/keyboard",
       "//sky/services/engine:engine_java",
       "//sky/services/oknet",
+      "//sky/services/intents:intents_lib",
     ]
   }
 
   copy_ex("assets") {
     clear_dir = true
     dest = "$root_build_dir/sky_shell/assets"
     sources = [
       "$root_build_dir/icudtl.dat",
     ]
     deps = [
@@ skipping 55 matching lines @@
     ]
 
     deps = common_deps + [
              ":common",
              "//sky/services/testing",
            ]
   }
 } else {
   assert(false, "Unsupported platform")
 }