Move printing operation to a new thread

Printing operations were blocking the UI thread, so applications
were irresponsive when printing in large size or high resolution.
Introduce a new worker for the painting logic and use shared pointers
to carry the data around and avoid copying PDF data between threads.

Task-number: QTBUG-68561
Change-Id: I30633380b75acd14f1a1df87985c99540168a9f1
Reviewed-by: Michael Brüning <michael.bruning@qt.io>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/webengine/api/qquickwebengineview.cpp b/src/webengine/api/qquickwebengineview.cpp
index d9667a643..e2a8b562d 100644
--- a/src/webengine/api/qquickwebengineview.cpp
+++ b/src/webengine/api/qquickwebengineview.cpp
@@ -1130,12 +1130,12 @@ void QQuickWebEngineViewPrivate::didFindText(quint64 requestId, int matchCount)
     callback.call(args);
 }
 
-void QQuickWebEngineViewPrivate::didPrintPage(quint64 requestId, const QByteArray &result)
+void QQuickWebEngineViewPrivate::didPrintPage(quint64 requestId, QSharedPointer<QByteArray> result)
 {
     Q_Q(QQuickWebEngineView);
     QJSValue callback = m_callbacks.take(requestId);
     QJSValueList args;
-    args.append(qmlEngine(q)->toScriptValue(result));
+    args.append(qmlEngine(q)->toScriptValue(*(result.data())));
     callback.call(args);
 }