Add data reduction functionality to all platforms.

components/data_reduction_proxy/browser/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.
 
 static_library("browser") {
   sources = [
     "data_reduction_proxy_auth_request_handler.cc",
     "data_reduction_proxy_auth_request_handler.h",
     "data_reduction_proxy_config_service.cc",
     "data_reduction_proxy_config_service.h",
     "data_reduction_proxy_configurator.h",
+    "data_reduction_proxy_delegate.cc",
+    "data_reduction_proxy_delegate.h",
     "data_reduction_proxy_metrics.cc",
     "data_reduction_proxy_metrics.h",
     "data_reduction_proxy_params.cc",
     "data_reduction_proxy_params.h",
     "data_reduction_proxy_prefs.cc",
     "data_reduction_proxy_prefs.h",
     "data_reduction_proxy_protocol.cc",
     "data_reduction_proxy_protocol.h",
     "data_reduction_proxy_settings.cc",
     "data_reduction_proxy_settings.h",
@@ skipping 46 matching lines @@
     "data_reduction_proxy_usage_stats_unittest.cc",
   ]
 
   deps = [
     ":browser",
     ":test_support",
     "//testing/gmock",
     "//testing/gtest",
   ]
 }