wasm: allow useCredentials access control to be set

Introduce UseCredentialsAttribute that indicates whether
the underlying fetch/XMLHttpRequest should use credentials
https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/withCredentials

Fixes: QTBUG-90893
Change-Id: I2c43e286db52df387c0a22737d027b9a2a8dd2d3
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

src/network/access/qnetworkreplywasmimpl.cpp

@@ -223,6 +223,9 @@ void QNetworkReplyWasmImplPrivate::doSendRequest()
             request.attribute(QNetworkRequest::CacheSaveControlAttribute, false).toBool()) {
         attr.attributes -= EMSCRIPTEN_FETCH_PERSIST_FILE;
     }
+    if (request.attribute(QNetworkRequest::UseCredentialsAttribute, true).toBool()) {
+        attr.withCredentials = true;
+    }
 
     attr.onsuccess = QNetworkReplyWasmImplPrivate::downloadSucceeded;
     attr.onerror = QNetworkReplyWasmImplPrivate::downloadFailed;

src/network/access/qnetworkrequest.cpp

@@ -305,6 +305,13 @@ QT_IMPL_METATYPE_EXTERN_TAGGED(QNetworkRequest::RedirectPolicy, QNetworkRequest_
         This attribute is ignored if the Http2AllowedAttribute is not set.
         (This value was introduced in 6.3.)
 
+    \value UseCredentialsAttribute
+        Requests only, type: QMetaType::Bool (default: false)
+        Indicates if the underlying XMLHttpRequest cross-site Access-Control
+        requests should be made using credentials. Has no effect on
+        same-origin requests. This only affects the WebAssembly platform.
+        (This value was introduced in 6.5.)
+
     \value User
         Special type. Additional information can be passed in
         QVariants with types ranging from User to UserMax. The default

src/network/access/qnetworkrequest.h

@@ -63,6 +63,7 @@ public:
         AutoDeleteReplyOnFinishAttribute,
         ConnectionCacheExpiryTimeoutSecondsAttribute,
         Http2CleartextAllowedAttribute,
+        UseCredentialsAttribute,
 
         User = 1000,
         UserMax = 32767