Introduce the image_decoder service

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 864 matching lines @@
 }
 
 group("gn_mojo_targets") {
   testonly = true
   if (is_linux && !is_chromeos) {
     # TODO(GYP): Figure out if any of these should be in gn_all
     # and figure out how cross-platform they are
     deps = [
       "//ipc:ipc_tests",
       "//mojo:tests",
+      "//services:service_unittests",
     ]
   }
 }
 
 group("gn_visibility") {
   deps = [
     "//build/config/sanitizers:options_sources",
     # "//third_party/pdfium:pdfium_embeddertests",  # TODO(GYP): visibility?
     # "//third_party/pdfium:pdfium_unittests",  # TODO(GYP): visibility?
   ]
@@ skipping 181 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" ]
 }