[ios] Added web::test::SetUpHttpServer which takes ResponseProvider.

ios/web/public/test/http_server_util.h

Index: ios/web/public/test/http_server_util.h
diff --git a/ios/web/public/test/http_server_util.h b/ios/web/public/test/http_server_util.h
index 77d403e443067f5655c84bf9d56e0d1d8475a458..a8b0b49bb80e4ac4be0e9a90f0690e5c98126e1a 100644
--- a/ios/web/public/test/http_server_util.h
+++ b/ios/web/public/test/http_server_util.h
@@ -10,6 +10,9 @@
 #include "url/gurl.h"
 
 namespace web {
+
+class ResponseProvider;
+
 namespace test {
 
 // Sets up a web::test::HttpServer with a simple HtmlResponseProvider. The
@@ -22,6 +25,10 @@ void SetUpSimpleHttpServer(const std::map<GURL, std::string>& responses);
 // a request.
 void SetUpFileBasedHttpServer();
 
+// Sets up a web::test::HttpServer with a single custom provider.
+// Takes ownership of the provider.
+void SetUpHttpServer(std::unique_ptr<web::ResponseProvider> provider);
+
 }  // namespace test
 }  // namespace web