Create Tether Chrome OS component and add a skeleton Initializer class.

BUILD.gn

 # Copyright (c) 2013 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.
 
 # This is the root build file for GN. GN will start processing by loading this
 # file, and recursively load all dependencies until all dependencies are either
 # resolved or known not to exist (which will cause the build to fail). So if
 # you add a new build file, there must be some path of dependencies from this
 # file to your new one or GN won't know about it.
 
@@ skipping 463 matching lines @@
       "//breakpad:breakpad_unittests",
       "//breakpad:core-2-minidump",
       "//breakpad:generate_test_dump",
       "//breakpad:minidump-2-core",
     ]
   }
 
   if (is_chromeos) {
     deps += [
       "//chromeos:chromeos_unittests",
+      "//chromeos/components:chromeos_components_unittests",
       "//components/session_manager/core",
       "//ui/arc:ui_arc_unittests",
       "//ui/chromeos:ui_chromeos_unittests",
     ]
   }
 
   if (is_chromeos || is_mac || is_win) {
     deps += [
       "//rlz:rlz_id",
       "//rlz:rlz_lib",
@@ skipping 605 matching lines @@
   assert(target_name != "")  # Mark as used.
   sources = invoker.actual_sources
   assert(
       sources == invoker.actual_sources,
       "Do not use a platform name in your output directory (found \"$root_build_dir\"). http://crbug.com/548283")
 }
 
 assert_valid_out_dir("_unused") {
   actual_sources = [ "$root_build_dir/foo" ]
 }