WebDriver: Implement Close Window closer to the spec

We are expected to return the list of open handles after closing the
current handle. Also just return a WebDriver::Response instead of a
wrapped Error variant.

Userland/Services/WebDriver/Client.cpp

@@ -559,8 +559,8 @@ Web::WebDriver::Response Client::handle_close_window(Vector<StringView> const& p
 {
     dbgln_if(WEBDRIVER_DEBUG, "Handling DELETE /session/<session_id>/window");
     auto* session = TRY(find_session_with_id(parameters[0]));
-    TRY(unwrap_result(session->close_window()));
+    auto result = TRY(session->close_window());
-    return make_json_value(JsonValue());
+    return make_json_value(result);
 }
 
 // 11.4 Get Window Handles, https://w3c.github.io/webdriver/#dfn-get-window-handles

Userland/Services/WebDriver/Client.h

@@ -95,29 +95,6 @@ private:
     ErrorOr<NonnullOwnPtr<Session>, Web::WebDriver::Error> take_session_with_id(StringView session_id);
     JsonValue make_json_value(JsonValue const&);
 
-    template<typename T>
-    static ErrorOr<T, Web::WebDriver::Error> unwrap_result(ErrorOr<T, Variant<Web::WebDriver::Error, Error>> result)
-    {
-        if (result.is_error()) {
-            Variant<Web::WebDriver::Error, Error> error = result.release_error();
-            if (error.has<Web::WebDriver::Error>())
-                return error.get<Web::WebDriver::Error>();
-            return Web::WebDriver::Error::from_code(Web::WebDriver::ErrorCode::UnsupportedOperation, error.get<Error>().string_literal());
-        }
-
-        return result.release_value();
-    }
-    static ErrorOr<void, Web::WebDriver::Error> unwrap_result(ErrorOr<void, Variant<Web::WebDriver::Error, Error>> result)
-    {
-        if (result.is_error()) {
-            Variant<Web::WebDriver::Error, Error> error = result.release_error();
-            if (error.has<Web::WebDriver::Error>())
-                return error.get<Web::WebDriver::Error>();
-            return Web::WebDriver::Error::from_code(Web::WebDriver::ErrorCode::UnsupportedOperation, error.get<Error>().string_literal());
-        }
-        return {};
-    }
-
     NonnullOwnPtr<Core::Stream::BufferedTCPSocket> m_socket;
     static Vector<Route> s_routes;
     String m_prefix = "/";

Userland/Services/WebDriver/Session.cpp

@@ -142,23 +142,22 @@ Web::WebDriver::Response Session::get_window_handle()
 }
 
 // 11.2 Close Window, https://w3c.github.io/webdriver/#dfn-close-window
-ErrorOr<void, Variant<Web::WebDriver::Error, Error>> Session::close_window()
+Web::WebDriver::Response Session::close_window()
 {
     // 1. If the current top-level browsing context is no longer open, return error with error code no such window.
     TRY(check_for_open_top_level_browsing_context_or_return_error());
 
-    // 2. Close the current top-level browsing context.
+    // FIXME: 2. Handle any user prompts and return its value if it is an error.
+
+    // 3. Close the current top-level browsing context.
     m_windows.remove(m_current_window_handle);
 
-    // 3. If there are no more open top-level browsing contexts, then close the session.
+    // 4. If there are no more open top-level browsing contexts, then close the session.
-    if (m_windows.is_empty()) {
+    if (m_windows.is_empty())
-        auto result = stop();
+        TRY(stop());
-        if (result.is_error()) {
-            return Variant<Web::WebDriver::Error, Error>(result.release_error());
-        }
-    }
 
-    return {};
+    // 5. Return the result of running the remote end steps for the Get Window Handles command.
+    return get_window_handles();
 }
 
 // 11.4 Get Window Handles, https://w3c.github.io/webdriver/#dfn-get-window-handles

Userland/Services/WebDriver/Session.h

@@ -48,7 +48,7 @@ public:
     ErrorOr<void> start();
     Web::WebDriver::Response stop();
     Web::WebDriver::Response get_window_handle();
-    ErrorOr<void, Variant<Web::WebDriver::Error, Error>> close_window();
+    Web::WebDriver::Response close_window();
     Web::WebDriver::Response get_window_handles() const;
     Web::WebDriver::Response take_element_screenshot(StringView element_id);