Windows QPA: Increase API level to 0x600 (Windows Vista).

- Directly link against dwmapi which should be present on
  Windows Vista and remove duplicated header constants.
- Remove struct QWindowsShell32DL since all required functions
  are present on Windows Vista.
- Remove functions that are no longer needed from QWindowsUser32DLL
  with exception of the clipboard functions which are not present
  in the MinGW stub libraries until v5.

Task-number: QTBUG-51673
Change-Id: Ia4a8a3f1db0f0d02322317d547e61ae39f9008b5
Reviewed-by: Oliver Wolff <oliver.wolff@theqtcompany.com>

1 files changed, 9 insertions, 13 deletions

diff --git a/src/plugins/platforms/windows/qwindowsbackingstore.cpp b/src/plugins/platforms/windows/qwindowsbackingstore.cpp
index df6749ad25..2d5e4071bc 100644
--- a/src/plugins/platforms/windows/qwindowsbackingstore.cpp
+++ b/src/plugins/platforms/windows/qwindowsbackingstore.cpp
@@ -100,19 +100,15 @@ void QWindowsBackingStore::flush(QWindow *window, const QRegion &region,
         POINT ptDst = {r.x(), r.y()};
         POINT ptSrc = {0, 0};
         BLENDFUNCTION blend = {AC_SRC_OVER, 0, BYTE(qRound(255.0 * rw->opacity())), AC_SRC_ALPHA};
-        if (QWindowsContext::user32dll.updateLayeredWindowIndirect) {
-            RECT dirty = {dirtyRect.x(), dirtyRect.y(),
-                dirtyRect.x() + dirtyRect.width(), dirtyRect.y() + dirtyRect.height()};
-            UPDATELAYEREDWINDOWINFO info = {sizeof(info), NULL, &ptDst, &size, m_image->hdc(), &ptSrc, 0, &blend, ULW_ALPHA, &dirty};
-            const BOOL result = QWindowsContext::user32dll.updateLayeredWindowIndirect(rw->handle(), &info);
-            if (!result)
-                qErrnoWarning("UpdateLayeredWindowIndirect failed for ptDst=(%d, %d),"
-                              " size=(%dx%d), dirty=(%dx%d %d, %d)", r.x(), r.y(),
-                              r.width(), r.height(), dirtyRect.width(), dirtyRect.height(),
-                              dirtyRect.x(), dirtyRect.y());
-        } else {
-            QWindowsContext::user32dll.updateLayeredWindow(rw->handle(), NULL, &ptDst, &size, m_image->hdc(), &ptSrc, 0, &blend, ULW_ALPHA);
-        }
+        RECT dirty = {dirtyRect.x(), dirtyRect.y(),
+                      dirtyRect.x() + dirtyRect.width(), dirtyRect.y() + dirtyRect.height()};
+        UPDATELAYEREDWINDOWINFO info = {sizeof(info), NULL, &ptDst, &size, m_image->hdc(), &ptSrc, 0, &blend, ULW_ALPHA, &dirty};
+        const BOOL result = UpdateLayeredWindowIndirect(rw->handle(), &info);
+        if (!result)
+            qErrnoWarning("UpdateLayeredWindowIndirect failed for ptDst=(%d, %d),"
+                          " size=(%dx%d), dirty=(%dx%d %d, %d)", r.x(), r.y(),
+                          r.width(), r.height(), dirtyRect.width(), dirtyRect.height(),
+                          dirtyRect.x(), dirtyRect.y());
     } else {
         const HDC dc = rw->getDC();
         if (!dc) {