[ios] Implemented -[ShellEarlGrey loadURL:].

ios/web/shell/test/BUILD.gn

 # Copyright 2016 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("//ios/build/config.gni")
 import("//ios/third_party/earl_grey/ios_eg_test.gni")
 
 ios_eg_test("ios_web_shell_test") {
   sources = [
     "context_menu_egtest.mm",
@@ skipping 51 matching lines @@
     "app/navigation_test_util.h",
     "app/navigation_test_util.mm",
     "app/web_shell_test_util.h",
     "app/web_shell_test_util.mm",
     "app/web_view_interaction_test_util.h",
     "app/web_view_interaction_test_util.mm",
     "earl_grey/shell_actions.h",
     "earl_grey/shell_actions.mm",
     "earl_grey/shell_base_test_case.h",
     "earl_grey/shell_base_test_case.mm",
+    "earl_grey/shell_earl_grey.h",
+    "earl_grey/shell_earl_grey.mm",
     "earl_grey/shell_matchers.h",
     "earl_grey/shell_matchers.mm",
   ]
 }
 
 bundle_data("bundle") {
   visibility = [ ":ios_web_shell_test_host" ]
   sources = [
     "http_server_files/basic_navigation_test.html",
     "http_server_files/tall_page.html",
     "http_server_files/testpage.pdf",
   ]
   outputs = [
     "{{bundle_resources_dir}}/{{source_root_relative_dir}}/" +
         "{{source_file_part}}",
   ]
 }