[Android] Create a dummy app to upload to Appurify for gtests.

build/android/pylib/remote/device/dummy/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.
+
+import("//build/config/android/config.gni")
+import("//build/config/android/rules.gni")
+
+# GYP: //build/android/pylib/remote/device/dummy/dummy.gyp:remote_device_dummy_apk
+android_apk("remote_device_dummy_apk") {
+  android_manifest = "//build/android/AndroidManifest.xml"
+  java_files = [ "src/org/chromium/dummy/Dummy.java" ]
+  apk_name = "remote_device_dummy"
+  testonly = true
+}