[Win32] Avoid NPE when autoscaling is disabled on shell

When autoscaling is disabled for a shell, setLocation(), setBounds() and
setSize() can throw an NPE as they want to access the parent's zoom even
though there is no parent. This fixes the behavior by adding an
according null check.

Author: HeikoKlare

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

@@ -3298,7 +3298,7 @@ void setBoundsInPixels (int x, int y, int width, int height, int flags, boolean
 public void setBounds (Rectangle rect) {
 	checkWidget ();
 	if (rect == null) error (SWT.ERROR_NULL_ARGUMENT);
-	int zoom = autoScaleDisabled ? parent.getZoom() : getZoom();
+	int zoom = autoScaleDisabled && parent != null ? parent.getZoom() : getZoom();
 	setBoundsInPixels(Win32DPIUtils.pointToPixel(rect, zoom));
 }
 
@@ -3556,7 +3556,7 @@ public void setLayoutData (Object layoutData) {
  */
 public void setLocation (int x, int y) {
 	checkWidget ();
-	int zoom = autoScaleDisabled ? parent.getZoom() : getZoom();
+	int zoom = autoScaleDisabled && parent != null ? parent.getZoom() : getZoom();
 	x = DPIUtil.pointToPixel(x, zoom);
 	y = DPIUtil.pointToPixel(y, zoom);
 	setLocationInPixels(x, y);
@@ -3813,7 +3813,7 @@ public void setRegion (Region region) {
  */
 public void setSize (int width, int height) {
 	checkWidget ();
-	int zoom = autoScaleDisabled ? parent.getZoom() : getZoom();
+	int zoom = autoScaleDisabled && parent != null ? parent.getZoom() : getZoom();
 	width = DPIUtil.pointToPixel(width, zoom);
 	height = DPIUtil.pointToPixel(height, zoom);
 	setSizeInPixels(width, height);