Always use ChannelMojo for content child processes.

ipc/BUILD.gn

 # Copyright (c) 2012 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/nacl/config.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 import("//tools/ipc_fuzzer/ipc_fuzzer.gni")
 
 component("ipc") {
@@ skipping 69 matching lines @@
     "ipc_mojo_handle_attachment.h",
     "ipc_mojo_message_helper.cc",
     "ipc_mojo_message_helper.h",
     "ipc_mojo_param_traits.cc",
     "ipc_mojo_param_traits.h",
     "ipc_platform_file.cc",
     "ipc_platform_file.h",
     "ipc_platform_file_attachment_posix.cc",
     "ipc_platform_file_attachment_posix.h",
     "ipc_sender.h",
-    "ipc_switches.cc",
-    "ipc_switches.h",
     "ipc_sync_channel.cc",
     "ipc_sync_channel.h",
     "ipc_sync_message.cc",
     "ipc_sync_message.h",
     "ipc_sync_message_filter.cc",
     "ipc_sync_message_filter.h",
     "mach_port_attachment_mac.cc",
     "mach_port_attachment_mac.h",
     "mach_port_mac.cc",
     "mach_port_mac.h",
@@ skipping 189 matching lines @@
     public_deps = [
       ":ipc",
     ]
     deps = [
       "//base",
       "//base/test:test_support",
       "//testing/gtest",
     ]
   }
 }