Fix missing GN dependencies.

mojo/mojo_application_package.gni

 # 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("//third_party/mojo/src/mojo/public/mojo_application.gni")
 
 # Used for mojo applications that have resources. This creates a directory
 # named output_name with the following contents:
 #   output_name.mojo : the shared library
 #   resources        : resources
 template("mojo_application_package") {
   mojo_deps = []
   if (defined(invoker.deps)) {
     mojo_deps += invoker.deps
   }
 
   if (defined(invoker.resources)) {
     output_name = target_name
     if (defined(invoker.output_name)) {
       output_name = invoker.output_name
     }
 
-    copy("copy_mojo_application_resources") {
+    copy_step_name = "${target_name}__copy_resources"
+    copy(copy_step_name) {
       sources = invoker.resources
       outputs = [
         "$root_out_dir/$output_name/resources/{{source_file_part}}",
       ]
+      if (defined(invoker.testonly)) {
+        testonly = invoker.testonly
+      }
+      deps = mojo_deps
     }
-    mojo_deps += [ ":copy_mojo_application_resources" ]
+    mojo_deps += [ ":$copy_step_name" ]
   }
 
   mojo_native_application(target_name) {
     output_name = invoker.target_name
     if (defined(invoker.output_name)) {
       output_name = invoker.output_name
     }
     output_name = output_name + "/" + output_name
 
     deps = mojo_deps
@@ skipping 59 matching lines @@
       public = invoker.public
     }
     if (defined(invoker.sources)) {
       sources = invoker.sources
     }
     if (defined(invoker.testonly)) {
       testonly = invoker.testonly
     }
   }
 }