Android: Do not build any extensions code except for extensions_constants.

chrome/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.
 
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//components/nacl/nacl_defines.gni")
 # //build/config/android/rules.gni imports //tools/grit/grit_rule.gni, which
 # produces a conflict for the "grit" template so we have to only include one.
@@ skipping 249 matching lines @@
     ]
     sources += rebase_path(gypi_values.chrome_browser_extensions_sources,
                            ".", "//chrome")
   }
   if (enable_background) {
     sources += rebase_path(gypi_values.chrome_browser_background_sources,
                            ".", "//chrome")
     if (!use_aura || is_win || is_chromeos) {
       sources -= [ "background/background_mode_manager_aura.cc" ]
     }
+    defines += [ "ENABLE_BACKGROUND=1" ]
   }
   if (enable_task_manager) {
     sources += rebase_path(gypi_values.chrome_browser_task_manager_sources,
                            ".", "//chrome")
   }
   if (enable_spellcheck) {
     sources += rebase_path(gypi_values.chrome_browser_spellchecker_sources,
                            ".", "//chrome")
     deps += [ "//third_party/hunspell" ]
   }
@@ skipping 456 matching lines @@
     "browsing_data/mock_browsing_data_local_storage_helper.cc",
     "browsing_data/mock_browsing_data_local_storage_helper.h",
     "browsing_data/mock_browsing_data_quota_helper.cc",
     "browsing_data/mock_browsing_data_quota_helper.h",
     "browsing_data/mock_browsing_data_service_worker_helper.cc",
     "browsing_data/mock_browsing_data_service_worker_helper.h",
     "download/download_test_file_activity_observer.cc",
     "download/download_test_file_activity_observer.h",
     "download/test_download_shelf.cc",
     "download/test_download_shelf.h",
-    "extensions/extension_action_test_util.cc",
-    "extensions/extension_action_test_util.h",
     "invalidation/fake_invalidation_service.cc",
     "invalidation/fake_invalidation_service.h",
     "media/fake_desktop_media_list.cc",
     "media/fake_desktop_media_list.h",
     "net/dns_probe_test_util.cc",
     "net/dns_probe_test_util.h",
     "net/url_request_mock_util.cc",
     "net/url_request_mock_util.h",
     "notifications/notification_test_util.cc",
     "notifications/notification_test_util.h",
@@ skipping 54 matching lines @@
   ]
 
   if (!is_ios) {
     deps += [
       "//components/sessions:test_support",
       "//google_apis:test_support",
     ]
   }
 
   if (enable_extensions) {
+    sources += [
+      "extensions/extension_action_test_util.cc",
+      "extensions/extension_action_test_util.h",
+    ]
     deps += [
       "//extensions:test_support",
     ]
   }
 
   if (is_chromeos) {
     sources += [
       "chromeos/app_mode/fake_cws.cc",
       "chromeos/app_mode/fake_cws.h",
       "chromeos/file_manager/fake_disk_mount_manager.cc",
@@ skipping 109 matching lines @@
     ]
   }
 
   if (enable_wifi_bootstrapping) {
     sources += [
       "local_discovery/wifi/mock_wifi_manager.cc",
       "local_discovery/wifi/mock_wifi_manager.h",
     ]
   }
 }