Fix external_application_unittests and add to mojob.py

mojo/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("//build/config/ui.gni")
 import("//mojo/public/mojo.gni")
 
 # TODO(beng): this meta target should probably move to the root dir's BUILD.gn.
 group("mojo") {
   # Meta-target, don't link into production code.
@@ skipping 71 matching lines @@
     "//mojo/services/clipboard:clipboard_unittests",
     "//mojo/services/network:apptests",
     "//mojo/services/network:unittests",
     "//mojo/shell:mojo_shell_tests",
     "//mojo/tools:message_generator",
     "//services/js:js_services_unittests",
   ]
 
   if (!is_win) {
     deps += [
-      "//mojo/shell:external_application_tests",
+      "//mojo/shell:external_application_unittests",
     ]
   }
 
   if (use_aura) {
     deps += [
       "//mojo/services/public/cpp/view_manager/tests:mojo_view_manager_lib_unittests",
       "//mojo/services/view_manager:view_manager_unittests",
       "//mojo/services/view_manager:view_manager_server_apptests",
       "//mojo/services/window_manager:window_manager_unittests",
     ]
   }
 }
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 
   generate_jni("jni_headers") {
     sources = [
       "android/javatests/src/org/chromium/mojo/MojoTestCase.java",
       "android/javatests/src/org/chromium/mojo/bindings/ValidationTestUtil.java",
       "android/system/src/org/chromium/mojo/system/impl/CoreImpl.java",
       "services/native_viewport/android/src/org/chromium/mojo/PlatformViewportAndroid.java",
     ]
 
     jni_package = "mojo"
   }
 }