Split up ios/web:test_support.

ios/web/public/test/http_server/http_server_util.h

Index: ios/web/public/test/http_server/http_server_util.h
diff --git a/ios/web/public/test/http_server_util.h b/ios/web/public/test/http_server/http_server_util.h
similarity index 89%
copy from ios/web/public/test/http_server_util.h
copy to ios/web/public/test/http_server/http_server_util.h
index b66356983795e34f89f4f85d475ff2df8bbf43f1..49cdc230ce00f3509239c1aa078bc028227987a4 100644
--- a/ios/web/public/test/http_server_util.h
+++ b/ios/web/public/test/http_server/http_server_util.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef IOS_WEB_PUBLIC_TEST_HTTP_SERVER_UTIL_H_
-#define IOS_WEB_PUBLIC_TEST_HTTP_SERVER_UTIL_H_
+#ifndef IOS_WEB_PUBLIC_TEST_HTTP_SERVER_HTTP_SERVER_UTIL_H_
+#define IOS_WEB_PUBLIC_TEST_HTTP_SERVER_HTTP_SERVER_UTIL_H_
 
 #include <map>
 
@@ -43,4 +43,4 @@ void AddResponseProvider(std::unique_ptr<web::ResponseProvider> provider);
 }  // namespace test
 }  // namespace web
 
-#endif  // IOS_WEB_PUBLIC_TEST_HTTP_SERVER_UTIL_H_
+#endif  // IOS_WEB_PUBLIC_TEST_HTTP_SERVER_HTTP_SERVER_UTIL_H_