Remove the _cpp_sources target from mojom.

components/test_runner/BUILD.gn

 # Copyright 2015 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")
 if (is_android) {
   import("//build/config/android/config.gni")
 }
 
@@ skipping 98 matching lines @@
   deps = [
     ":resources",
     "//base:base",
     "//base:i18n",
     "//cc",
     "//cc/blink",
     "//content/public/common",
     "//gin",
     "//gpu",
     "//gpu/command_buffer/client:gles2_interface",
-    "//media/midi:mojo_cpp_sources",
+    "//media/midi:mojo",
     "//net",
     "//skia",
     "//third_party/WebKit/public:blink",
     "//ui/display",
     "//ui/events:dom_keycode_converter",
     "//ui/events:events_base",
     "//ui/events/blink",
     "//ui/gfx",
     "//ui/gfx:test_support",
     "//ui/gfx/geometry",
@@ skipping 74 matching lines @@
 
   if (use_x11) {
     deps += [ ":copy_x11_fonts" ]
     data_deps += [ ":copy_x11_fonts" ]
   }
   if (is_android) {
     deps += [ ":copy_android_fonts" ]
     data_deps += [ ":copy_android_fonts" ]
   }
 }