Refactor AO2TS to make it easier to componentize.

google_apis/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("//testing/test.gni")
 
 declare_args() {
   # You can set the variable 'use_official_google_api_keys' to true
   # to use the Google-internal file containing official API keys
@@ skipping 95 matching lines @@
     "gaia/oauth2_access_token_fetcher_immediate_error.cc",
     "gaia/oauth2_access_token_fetcher_immediate_error.h",
     "gaia/oauth2_access_token_fetcher_impl.cc",
     "gaia/oauth2_access_token_fetcher_impl.h",
     "gaia/oauth2_api_call_flow.cc",
     "gaia/oauth2_api_call_flow.h",
     "gaia/oauth2_mint_token_flow.cc",
     "gaia/oauth2_mint_token_flow.h",
     "gaia/oauth2_token_service.cc",
     "gaia/oauth2_token_service.h",
+    "gaia/oauth2_token_service_delegate.cc",
+    "gaia/oauth2_token_service_delegate.h",
     "gaia/oauth2_token_service_request.cc",
     "gaia/oauth2_token_service_request.h",
     "gaia/oauth_request_signer.cc",
     "gaia/oauth_request_signer.h",
     "gaia/ubertoken_fetcher.cc",
     "gaia/ubertoken_fetcher.h",
     "google_api_keys.cc",
     "google_api_keys.h",
   ]
 
@@ skipping 39 matching lines @@
   }
 }
 
 source_set("test_support") {
   testonly = true
   sources = [
     "gaia/fake_gaia.cc",
     "gaia/fake_gaia.h",
     "gaia/fake_identity_provider.cc",
     "gaia/fake_identity_provider.h",
+    "gaia/fake_oauth2_token_service_delegate.cc",
+    "gaia/fake_oauth2_token_service_delegate.h",
     "gaia/fake_oauth2_token_service.cc",
     "gaia/fake_oauth2_token_service.h",
     "gaia/mock_url_fetcher_factory.h",
     "gaia/oauth2_token_service_test_util.cc",
     "gaia/oauth2_token_service_test_util.h",
   ]
 
   public_deps = [
     "//base",
     "//base/test:test_support",
@@ skipping 46 matching lines @@
       "drive/base_requests_unittest.cc",
       "drive/drive_api_parser_unittest.cc",
       "drive/drive_api_requests_unittest.cc",
       "drive/drive_api_url_generator_unittest.cc",
       "drive/request_sender_unittest.cc",
       "drive/request_util_unittest.cc",
       "drive/time_util_unittest.cc",
     ]
   }
 }