Make MB aware of iOS bot configs and get iOS working.

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.
 
+# GN build of //ios/web only supports building with the web implementation of
+# WebThread as opposed to GYP build that allow using a shim implementation based
+# on top of BrowserThread.
+#
+# See ios/web/ios_web.gyp for more information on how gyp supports this. The
+# gn targets will fold the target selection in the gyp "incomplete" targets.
+
 import("//testing/test.gni")
 import("//ios/web/js_compile.gni")
 
 config("config") {
   visibility = [ ":web" ]
 
   # The WebKit framework is only available since iOS 8.0 but Chrome on iOS do
   # supports iOS 7.0 so need to use weak linking.
   # TODO(crbug.com/541549): change to regular linking once support for iOS 7 is
   # dropped.
   ldflags = [
     "-weak_framework",
     "WebKit",
   ]
 }
 
 source_set("web") {
   deps = [
+    ":core",
+    ":js_resources",
+    ":user_agent",
     "//base",
     "//components/url_formatter",
     "//ios/net",
     "//ios/third_party/blink:html_tokenizer",
     "//net",
     "//ui/base",
     "//ui/gfx",
     "//ui/gfx/geometry:geometry",
     "//ui/resources",
     "//url",
-    ":core",
-    ":js_resources",
-    ":user_agent",
   ]
 
   sources = [
     "active_state_manager_impl.h",
     "active_state_manager_impl.mm",
     "alloc_with_zone_interceptor.h",
     "alloc_with_zone_interceptor.mm",
     "browser_state.mm",
     "browser_url_rewriter_impl.cc",
     "browser_url_rewriter_impl.h",
@@ skipping 276 matching lines @@
 }
 
 source_set("test_support") {
   testonly = true
 
   deps = [
     "//ios/testing:ocmock_support",
     "//ios/third_party/gcdwebserver",
     "//testing/gmock",
     "//testing/gtest",
+    "//third_party/google_toolbox_for_mac",
     "//third_party/ocmock",
     ":web",
   ]
 
   sources = [
     "public/test/crw_test_js_injection_receiver.h",
     "public/test/crw_test_js_injection_receiver.mm",
     "public/test/http_server.h",
     "public/test/http_server.mm",
     "public/test/js_test_util.h",
@@ skipping 27 matching lines @@
     "test/web_test_suite.h",
     "test/wk_web_view_crash_utils.h",
     "test/wk_web_view_crash_utils.mm",
   ]
 }
 
 test("ios_web_unittests") {
   deps = [
     "//base",
     "//base/test:test_support",
-    "//ios/testing:ocmock_support",
     "//net:test_support",
     "//testing/gmock",
     "//testing/gtest",
+    "//third_party/google_toolbox_for_mac",
     "//third_party/ocmock",
     "//ui/base:test_support",
+    "//ios/testing:ocmock_support",
+    ":web",
     ":test_support",
-    ":web",
   ]
 
   sources = [
     "active_state_manager_impl_unittest.mm",
     "alloc_with_zone_interceptor_unittest.mm",
     "browser_state_unittest.cc",
     "browsing_data_partition_impl_unittest.mm",
     "crw_browsing_data_store_unittest.mm",
     "crw_network_activity_indicator_manager_unittest.mm",
     "history_state_util_unittest.mm",
     "navigation/crw_session_controller_unittest.mm",
     "navigation/crw_session_entry_unittest.mm",
     "navigation/navigation_item_impl_unittest.mm",
     "navigation/navigation_manager_impl_unittest.mm",
     "navigation/nscoder_util_unittest.mm",
-    "net/cert_host_pair_unittest.cc",
     "net/cert_policy_unittest.cc",
     "net/cert_verifier_block_adapter_unittest.cc",
     "net/clients/crw_csp_network_client_unittest.mm",
     "net/clients/crw_js_injection_network_client_unittest.mm",
     "net/clients/crw_passkit_network_client_unittest.mm",
     "net/crw_cert_verification_controller_unittest.mm",
     "net/crw_url_verifying_protocol_handler_unittest.mm",
     "net/request_group_util_unittest.mm",
     "net/request_tracker_impl_unittest.mm",
     "net/web_http_protocol_handler_delegate_unittest.mm",
     "public/referrer_util_unittest.cc",
+    "public/test/http_server_unittest.mm",
     "string_util_unittest.cc",
     "test/crw_fake_web_controller_observer_unittest.mm",
     "test/run_all_unittests.cc",
     "ui_web_view_util_unittest.mm",
     "url_scheme_util_unittest.mm",
     "url_util_unittest.cc",
     "weak_nsobject_counter_unittest.mm",
     "web_state/crw_web_view_scroll_view_proxy_unittest.mm",
     "web_state/js/common_js_unittest.mm",
     "web_state/js/core_js_unittest.mm",
@@ skipping 65 matching lines @@
     ":web_bundle_ui",
     ":web_bundle_wk",
   ]
 
   sources = [
     "web_state/js/resources/plugin_placeholder.js",
     "web_state/js/resources/window_id.js",
     "webui/resources/web_ui.js",
   ]
 }