[ios] Added web// public API to let embedder observe loading progress.

ios/web/BUILD.gn

 # Copyright 2015 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("//testing/test.gni")
 import("//ios/web/js_compile.gni")
 
 source_set("web") {
   deps = [
     ":core",
@@ skipping 146 matching lines @@
     "public/web_state/page_display_state.h",
     "public/web_state/page_display_state.mm",
     "public/web_state/ui/crw_content_view.h",
     "public/web_state/ui/crw_generic_content_view.h",
     "public/web_state/ui/crw_native_content.h",
     "public/web_state/ui/crw_native_content_provider.h",
     "public/web_state/ui/crw_web_delegate.h",
     "public/web_state/ui/crw_web_view_content_view.h",
     "public/web_state/url_verification_constants.h",
     "public/web_state/web_state.h",
+    "public/web_state/web_state_delegate.h",
+    "public/web_state/web_state_delegate_bridge.h",
     "public/web_state/web_state_observer.h",
     "public/web_state/web_state_observer_bridge.h",
     "public/web_state/web_state_policy_decider.h",
     "public/web_state/web_state_user_data.h",
     "public/web_thread.h",
     "public/web_thread_delegate.h",
     "public/web_ui_ios_data_source.h",
     "public/web_view_counter.h",
     "public/web_view_creation_util.h",
     "public/web_view_type.h",
@@ skipping 57 matching lines @@
     "web_state/ui/crw_wk_web_view_web_controller.mm",
     "web_state/ui/web_view_js_utils.h",
     "web_state/ui/web_view_js_utils.mm",
     "web_state/ui/wk_back_forward_list_item_holder.h",
     "web_state/ui/wk_back_forward_list_item_holder.mm",
     "web_state/ui/wk_web_view_configuration_provider.h",
     "web_state/ui/wk_web_view_configuration_provider.mm",
     "web_state/web_controller_observer_bridge.h",
     "web_state/web_controller_observer_bridge.mm",
     "web_state/web_state.mm",
+    "web_state/web_state_delegate.mm",
+    "web_state/web_state_delegate_bridge.mm",
     "web_state/web_state_facade_delegate.h",
     "web_state/web_state_impl.h",
     "web_state/web_state_impl.mm",
     "web_state/web_state_observer.mm",
     "web_state/web_state_observer_bridge.mm",
     "web_state/web_state_policy_decider.mm",
     "web_state/web_state_weak_ptr_factory.h",
     "web_state/web_state_weak_ptr_factory.mm",
     "web_state/web_view_internal_creation_util.h",
     "web_state/web_view_internal_creation_util.mm",
@@ skipping 170 matching lines @@
     "web_state/js/crw_js_window_id_manager_unittest.mm",
     "web_state/js/page_script_util_unittest.mm",
     "web_state/ui/crw_static_file_web_view_unittest.mm",
     "web_state/ui/crw_web_controller_container_view_unittest.mm",
     "web_state/ui/crw_web_controller_observer_unittest.mm",
     "web_state/ui/crw_web_controller_unittest.mm",
     "web_state/ui/crw_wk_script_message_router_unittest.mm",
     "web_state/ui/web_view_js_utils_unittest.mm",
     "web_state/ui/wk_back_forward_list_item_holder_unittest.mm",
     "web_state/ui/wk_web_view_configuration_provider_unittest.mm",
+    "web_state/web_state_delegate_bridge_unittest.mm",
+    "web_state/web_state_delegate_stub.h",
+    "web_state/web_state_delegate_stub.mm",
     "web_state/web_state_impl_unittest.mm",
     "web_state/web_view_internal_creation_util_unittest.mm",
     "web_state/wk_web_view_security_util_unittest.mm",
     "web_view_counter_impl_unittest.mm",
     "webui/crw_web_ui_manager_unittest.mm",
     "webui/crw_web_ui_page_builder_unittest.mm",
     "webui/url_fetcher_block_adapter_unittest.mm",
   ]
 }
 
@@ skipping 32 matching lines @@
   public_deps = [
     ":web_bundle",
   ]
 
   sources = [
     "web_state/js/resources/plugin_placeholder.js",
     "web_state/js/resources/window_id.js",
     "webui/resources/web_ui.js",
   ]
 }