Remove all service manifests from data_deps

mash/webtest/BUILD.gn

 # Copyright 2016 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/ui.gni")
 import("//services/service_manager/public/cpp/service.gni")
 import("//services/service_manager/public/service_manifest.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//tools/grit/repack.gni")
 
@@ skipping 32 matching lines @@
     "main.cc",
   ]
 
   deps = [
     ":lib",
     "//services/service_manager/public/cpp",
     "//ui/views/mus:for_mojo_application",
   ]
 
   resources = [ "$root_out_dir/views_mus_resources.pak" ]
-
-  data_deps = [
-    ":manifest",
-  ]
 }
 
 service_manifest("manifest") {
   name = "webtest"
   source = "manifest.json"
 }