Split up ios/web:test_support.

ios/web/web_state/navigation_callbacks_inttest.mm

 // Copyright 2017 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.
 
 #include <memory>
 #include <string>
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/stringprintf.h"
 #import "ios/web/public/navigation_item.h"
 #import "ios/web/public/navigation_manager.h"
-#import "ios/web/public/test/http_server.h"
-#include "ios/web/public/test/http_server_util.h"
+#import "ios/web/public/test/http_server/http_server.h"
+#include "ios/web/public/test/http_server/http_server_util.h"
 #import "ios/web/public/web_state/navigation_context.h"
 #include "ios/web/public/web_state/web_state_observer.h"
 #include "ios/web/test/test_url_constants.h"
 #import "ios/web/test/web_int_test.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/page_transition_types.h"
 #include "url/gurl.h"
 #include "url/scheme_host_port.h"
 
@@ skipping 602 matching lines @@
   // delegate does not run callback for ShowRepostFormWarningDialog. Clearing
   // the delegate will allow form resubmission. Remove this workaround (clearing
   // the delegate, once |check_for_repost| is supported).
   web_state()->SetDelegate(nullptr);
   ExecuteBlockAndWaitForLoad(action, ^{
     navigation_manager()->GoForward();
   });
 }
 
 }  // namespace web