Add chromeos test data dir for unit_tests

chrome/browser/chromeos/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("//chrome/chrome_tests.gni")
 import("//media/media_options.gni")
 import("//third_party/protobuf/proto_library.gni")
 
@@ skipping 191 matching lines @@
     "//dbus",
     "//mojo/public/cpp/system:system",
     "//skia",
     "//sync",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/icu",
     "//third_party/leveldatabase",
     "//ui/chromeos/resources",
   ]
+  data = [
+    "//chromeos/test/data/",
+  ]
 }
 
 proto_library("device_policy_proto") {
   sources = [
     "policy/proto/chrome_device_policy.proto",
     "policy/proto/install_attributes.proto",
   ]
 }
 
 proto_library("attestation_proto") {
   sources = [
     "attestation/attestation_key_payload.proto",
     "attestation/attestation_signed_data.proto",
   ]
 }