Remove the _cpp_sources target from mojom.

content/renderer/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("//media/media_options.gni")
 import("//ppapi/features/features.gni")
 import("//printing/features/features.gni")
 import("//third_party/webrtc/build/webrtc.gni")
@@ skipping 414 matching lines @@
     "//gpu",
     "//gpu/command_buffer/client:gles2_interface",
     "//jingle:jingle_glue",
     "//media",
     "//media/blink",
     "//media/capture",
     "//media/gpu",
     "//media/gpu/ipc/client",
     "//media/gpu/ipc/common",
     "//media/midi",
-    "//media/midi:mojo_cpp_sources",
+    "//media/midi:mojo",
     "//media/mojo/interfaces:remoting",
     "//mojo/common",
     "//mojo/edk/js",
     "//mojo/public/cpp/bindings",
     "//mojo/public/js",
     "//net",
     "//ppapi/features",
     "//printing/features",
     "//sandbox",
     "//services/service_manager/public/cpp",
@@ skipping 470 matching lines @@
     # For the defines in mojo_media_config.
     public_configs = [ "//media/mojo/services:mojo_media_config" ]
   }
 
   if (!is_component_build) {
     public_deps = [
       ":renderer",
     ]
   }
 }