Replace ChildProcess/AppChildProcess with a simple ChildMain().

shell/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")
 import("//mojo/public/mojo_application.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//mojo/tools/embed/rules.gni")
 import("//testing/test.gni")
@@ skipping 113 matching lines @@
     "//shell/application_manager",
   ]
 
   deps = [
     "//base",
   ]
 }
 
 source_set("lib") {
   sources = [
-    "app_child_process.cc",
-    "app_child_process.h",
-    "child_process.cc",
-    "child_process.h",
+    "child_main.cc",
+    "child_main.h",
     "child_process_host.cc",
     "child_process_host.h",
     "command_line_util.cc",
     "command_line_util.h",
     "context.cc",
     "context.h",
     "external_application_listener.cc",
     "external_application_listener.h",
     "filename_util.cc",
     "filename_util.h",
@@ skipping 414 matching lines @@
     "//mojo/public/cpp/system:system",
     "//mojo/services/http_server/public/cpp",
     "//mojo/services/http_server/public/interfaces",
     "//mojo/services/network/public/interfaces",
     "//shell/test:bindings",
     ":embed_pingable",
   ]
 
   data_deps = [ "//services/http_server:http_server($default_toolchain)" ]
 }