Merge remote branch 'origin/4.6' into qt-4.7-from-4.6

Conflicts:
	qmake/generators/symbian/symmake.cpp
	src/gui/image/qimage.cpp
	src/openvg/qwindowsurface_vgegl.cpp

2 files changed, 4 insertions, 0 deletions

diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index ce1d6d3..d226baf 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -5709,6 +5709,9 @@ void QImage::setAlphaChannel(const QImage &alphaChannel)
     else
         *this = convertToFormat(QImage::Format_ARGB32_Premultiplied);
 
+    if (isNull())
+        return;
+
     // Slight optimization since alphachannels are returned as 8-bit grays.
     if (alphaChannel.d->depth == 8 && alphaChannel.isGrayscale()) {
         const uchar *src_data = alphaChannel.d->data;
diff --git a/src/gui/image/qimagewriter.cpp b/src/gui/image/qimagewriter.cpp
index a5f7b31..503a1b2 100644
--- a/src/gui/image/qimagewriter.cpp
+++ b/src/gui/image/qimagewriter.cpp
@@ -197,6 +197,7 @@ static QImageIOHandler *createWriteHandlerHelper(QIODevice *device,
         for (int i = 0; i < keys.size(); ++i) {
             QImageIOPlugin *plugin = qobject_cast<QImageIOPlugin *>(l->instance(keys.at(i)));
             if (plugin && (plugin->capabilities(device, testFormat) & QImageIOPlugin::CanWrite)) {
+                delete handler;
                 handler = plugin->create(device, testFormat);
                 break;
             }