Merge branch '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2 into 4.7-integration

* '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2:
  Fixed bug and performance problem in windowsstyle.
  Restored old flushing behavior in -graphicssystem opengl on desktop.

2 files changed, 6 insertions, 5 deletions

diff --git a/src/gui/styles/qwindowsstyle.cpp b/src/gui/styles/qwindowsstyle.cpp
index 32a6d8d..4144b80 100644
--- a/src/gui/styles/qwindowsstyle.cpp
+++ b/src/gui/styles/qwindowsstyle.cpp
@@ -1395,8 +1395,8 @@ void QWindowsStyle::drawPrimitive(PrimitiveElement pe, const QStyleOption *opt,
             if (!QPixmapCache::find(pixmapName, pixmap)) {
                 int border = size/5;
                 int sqsize = 2*(size/2);
-                QImage image(sqsize, sqsize, QImage::Format_ARGB32);
-                image.fill(Qt::transparent);
+                QImage image(sqsize, sqsize, QImage::Format_ARGB32_Premultiplied);
+                image.fill(0);
                 QPainter imagePainter(&image);
 
                 QPolygon a;
diff --git a/src/opengl/qwindowsurface_gl.cpp b/src/opengl/qwindowsurface_gl.cpp
index b8716ce..7243f02 100644
--- a/src/opengl/qwindowsurface_gl.cpp
+++ b/src/opengl/qwindowsurface_gl.cpp
@@ -520,9 +520,10 @@ void QGLWindowSurface::flush(QWidget *widget, const QRegion &rgn, const QPoint &
 
     // did_paint is set to true in ::beginPaint. ::beginPaint means that we
     // at least cleared the background (= painted something). In EGL API it's a
-    // mistakte to call swapBuffers if nothing was painted. This check protects
-    // the flush func from being executed if it's for nothing.
-    if (!d_ptr->did_paint)
+    // mistake to call swapBuffers if nothing was painted unless
+    // EGL_BUFFER_PRESERVED is set. This check protects the flush func from
+    // being executed if it's for nothing.
+    if (!hasPartialUpdateSupport() && !d_ptr->did_paint)
         return;
 
     QWidget *parent = widget->internalWinId() ? widget : widget->nativeParentWidget();