3 files changed, 13 insertions, 2 deletions
diff --git a/src/gui/painting/qbackingstore.cpp b/src/gui/painting/qbackingstore.cpp
index e5d8abc..a06a121 100644
--- a/src/gui/painting/qbackingstore.cpp
+++ b/src/gui/painting/qbackingstore.cpp
@@ -1143,9 +1143,9 @@ void QWidgetBackingStore::sync(QWidget *exposedWidget, const QRegion &exposedReg
         return;
     }
 
-    // If there's no partial update support we always need
+    // If there's no preserved contents support we always need
     // to do a full repaint before flushing
-    if (!windowSurface->hasPartialUpdateSupport())
+    if (!windowSurface->hasPreservedContents())
         fullUpdatePending = true;
 
     // Nothing to repaint.
diff --git a/src/gui/painting/qwindowsurface.cpp b/src/gui/painting/qwindowsurface.cpp
index 9b71818..050805e 100644
--- a/src/gui/painting/qwindowsurface.cpp
+++ b/src/gui/painting/qwindowsurface.cpp
@@ -332,6 +332,16 @@ bool QWindowSurface::hasPartialUpdateSupport() const
     return true;
 }
 
+/*!
+  Says whether the window surface's contents are preserved on flush.
+  If not, the window surface contents need to be fully repainted before the
+  next flush.
+*/
+bool QWindowSurface::hasPreservedContents() const
+{
+    return hasPartialUpdateSupport();
+}
+
 #ifdef Q_WS_QPA
 #define Q_EXPORT_SCROLLRECT Q_GUI_EXPORT
 #else
diff --git a/src/gui/painting/qwindowsurface_p.h b/src/gui/painting/qwindowsurface_p.h
index 4a2775f..95b2ee4 100644
--- a/src/gui/painting/qwindowsurface_p.h
+++ b/src/gui/painting/qwindowsurface_p.h
@@ -102,6 +102,7 @@ public:
 
     virtual bool hasStaticContentsSupport() const;
     virtual bool hasPartialUpdateSupport() const;
+    virtual bool hasPreservedContents() const;
 
     void setStaticContents(const QRegion &region);
     QRegion staticContents() const;