[Extensions] Propagate activeTab hosts to extension background pages

extensions/renderer/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")
 
 assert(enable_extensions)
 
 # GYP version: extensions/extensions.gyp:extensions_renderer
 source_set("renderer") {
@@ skipping 127 matching lines @@
     "script_injection_manager.h",
     "script_injector.h",
     "scripts_run_info.cc",
     "scripts_run_info.h",
     "send_request_natives.cc",
     "send_request_natives.h",
     "set_icon_natives.cc",
     "set_icon_natives.h",
     "static_v8_external_one_byte_string_resource.cc",
     "static_v8_external_one_byte_string_resource.h",
+    "tab_finder.cc",
+    "tab_finder.h",
     "test_features_native_handler.cc",
     "test_features_native_handler.h",
     "user_gestures_native_handler.cc",
     "user_gestures_native_handler.h",
     "user_script_injector.cc",
     "user_script_injector.h",
     "user_script_set.cc",
     "user_script_set.h",
     "user_script_set_manager.cc",
     "user_script_set_manager.h",
@@ skipping 12 matching lines @@
     "//gin",
     "//skia",
     "//third_party/WebKit/public:blink",
     "//third_party/mojo/src/mojo/edk/js",
   ]
 
   if (is_win) {
     cflags = [ "/wd4267" ]  # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
   }
 }