[win32] Update shell zoom before position change

When a Shell is moved to a new position, the new position can be located on a different monitor. If autoScaleOnRuntimeActive is active and the monitor has a different zoom than the previous one, this would lead to a wrong positioning of the shell due to the stored zoom of the shell. Therefor the Shell nativeZoom must update BEFORE the location change will be applied. This commit adds this behaviour on win32.

Contributes to #62 and #127

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Display.java

@@ -5251,4 +5251,15 @@ static String withCrLf (String string) {
 static boolean isActivateShellOnForceFocus() {
 	return "true".equals(System.getProperty("org.eclipse.swt.internal.activateShellOnForceFocus", "true")); //$NON-NLS-1$
 }
+
+Monitor getContainingMonitor(int x, int y) {
+	Monitor[] monitors = getMonitors();
+	for (Monitor current : monitors) {
+		Rectangle clientArea = current.getClientArea();
+		if (clientArea.contains(x, y)) {
+			return current;
+		}
+	}
+	return getPrimaryMonitor();
+}
 }

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Shell.java

@@ -1571,6 +1571,40 @@ public void setAlpha (int alpha) {
 	}
 }
 
+private void updateNativeZoomBeforePositionChange(int x, int y) {
+	if (DPIUtil.isAutoScaleOnRuntimeActive()) {
+		Monitor monitor = display.getContainingMonitor(x, y);
+		this.nativeZoom = monitor.zoom;
+		System.out.println("Update shell zoom (" + handle + ") " + monitor.zoom);
+	}
+}
+
+@Override
+public void setLocation(Point location) {
+	if (location == null) error (SWT.ERROR_NULL_ARGUMENT);
+	updateNativeZoomBeforePositionChange(location.x, location.y);
+	super.setLocation(location);
+}
+
+@Override
+public void setLocation(int x, int y) {
+	updateNativeZoomBeforePositionChange(x, y);
+	super.setLocation(x, y);
+}
+
+@Override
+public void setBounds(Rectangle rect) {
+	if (rect == null) error (SWT.ERROR_NULL_ARGUMENT);
+	updateNativeZoomBeforePositionChange(rect.x, rect.y);
+	super.setBounds(rect);
+}
+
+@Override
+public void setBounds(int x, int y, int width, int height) {
+	updateNativeZoomBeforePositionChange(x, y);
+	super.setBounds(x, y, width, height);
+}
+
 @Override
 void setBoundsInPixels (int x, int y, int width, int height, int flags, boolean defer) {
 	if (fullScreen) setFullScreen (false);