Stop linking in the old Mojo EDK.

ipc/mojo/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("//mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 
-mojom("client_channel") {
-  sources = [
-    "client_channel.mojom",
-  ]
-}
-
 component("mojo") {
   sources = [
     "async_handle_waiter.cc",
     "async_handle_waiter.h",
-    "client_channel.mojom",
     "ipc_channel_mojo.cc",
     "ipc_channel_mojo.h",
     "ipc_message_pipe_reader.cc",
     "ipc_message_pipe_reader.h",
     "ipc_mojo_bootstrap.cc",
     "ipc_mojo_bootstrap.h",
     "ipc_mojo_handle_attachment.cc",
     "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",
     "scoped_ipc_support.cc",
     "scoped_ipc_support.h",
   ]
 
   defines = [ "IPC_MOJO_IMPLEMENTATION" ]
 
   deps = [
-    ":client_channel",
     "//base",
     "//base/third_party/dynamic_annotations",
     "//ipc",
+    "//mojo/edk/system",
     "//mojo/environment:chromium",
     "//mojo/public/c/environment:environment",
     "//mojo/public/cpp/bindings",
-    "//third_party/mojo/src/mojo/edk/system",
   ]
 }
 
 test("ipc_mojo_unittests") {
   sources = [
     "async_handle_waiter_unittest.cc",
     "ipc_channel_mojo_unittest.cc",
     "ipc_mojo_bootstrap_unittest.cc",
     "run_all_unittests.cc",
   ]
 
   deps = [
     "//base",
     "//base/test:test_support",
     "//base/third_party/dynamic_annotations",
     "//ipc",
     "//ipc:test_support",
     "//ipc/mojo",
+    "//mojo/edk/system",
     "//mojo/environment:chromium",
     "//testing/gtest",
-    "//third_party/mojo/src/mojo/edk/system",
     "//url",
   ]
 }
 
 test("ipc_mojo_perftests") {
   sources = [
     "ipc_mojo_perftest.cc",
   ]
 
   deps = [
     "//base",
     "//base/test:test_support",
     "//base/test:test_support_perf",
     "//base/third_party/dynamic_annotations",
     "//ipc",
     "//ipc:test_support",
     "//ipc/mojo",
+    "//mojo/edk/system",
     "//mojo/environment:chromium",
-    "//third_party/mojo/src/mojo/edk/system",
     "//url",
   ]
 }