Remove the _cpp_sources target from mojom.

ui/views/mus/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/features.gni")
 import("//build/config/ui.gni")
 import("//services/service_manager/public/cpp/service.gni")
 import("//services/service_manager/public/service_manifest.gni")
 import("//testing/test.gni")
 import("//tools/grit/repack.gni")
@@ skipping 72 matching lines @@
     "//ui/display",
     "//ui/events",
     "//ui/events:events_base",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gfx/geometry/mojo",
     "//ui/gl",
     "//ui/native_theme",
     "//ui/platform_window",
     "//ui/platform_window/mojo",
-    "//ui/platform_window/mojo:interfaces_cpp_sources",
+    "//ui/platform_window/mojo:interfaces",
     "//ui/platform_window/stub",
     "//ui/views",
     "//ui/wm",
   ]
 
   if (is_linux && !is_android) {
     deps += [ "//components/font_service/public/cpp" ]
     data_deps = [
       "//components/font_service",
     ]
@@ skipping 305 matching lines @@
 
 service_manifest("unittests_aura_manifest") {
   name = "views_aura_mus_unittests"
   source = "unittests_aura_manifest.json"
 }
 
 service_manifest("interactive_ui_tests_manifest") {
   name = "views_mus_interactive_ui_tests"
   source = "interactive_ui_tests_manifest.json"
 }