[GTK4] Fix gtk_widget_measure warning

There is a flood of "(SWT:64178): Gtk-WARNING **: 12:04:34.730: Trying
to measure GtkHeaderBar 0x7fb13846ca30 for width of 0, but it needs at
least 137" like messages when developing. The issue is that
gtk_widget_measure is being called with for_size=0 param which happens
to be below the minimum size for many widgets. The documentation clearly
states "If no size is known, -1 can be passed." and so is done now.

Author: akurtakov

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

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2018 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -855,14 +855,14 @@ Point computeNativeSize (long h, int wHint, int hHint, boolean changed) {
 		int [] natural_size = new int [1];
 		if (wHint == SWT.DEFAULT) {
 			if (GTK.GTK4) {
-				GTK4.gtk_widget_measure(h, GTK.GTK_ORIENTATION_HORIZONTAL, height, null, natural_size, null, null);
+				GTK4.gtk_widget_measure(h, GTK.GTK_ORIENTATION_HORIZONTAL, height>0?height:-1, null, natural_size, null, null);
 			} else {
 				GTK3.gtk_widget_get_preferred_width_for_height (h, height, null, natural_size);
 			}
 			width = natural_size [0];
 		} else {
 			if (GTK.GTK4) {
-				GTK4.gtk_widget_measure(h, GTK.GTK_ORIENTATION_VERTICAL, width, null, natural_size, null, null);
+				GTK4.gtk_widget_measure(h, GTK.GTK_ORIENTATION_VERTICAL, width>0?width:-1, null, natural_size, null, null);
 			} else {
 				GTK3.gtk_widget_get_preferred_height_for_width (h, width, null, natural_size);
 			}

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

@@ -1862,7 +1862,7 @@ long gtk_size_allocate (long widget, long allocation) {
 			GDK.gdk_monitor_get_geometry(monitor, monitorSize);
 			long header = GTK4.gtk_widget_get_next_sibling(GTK4.gtk_widget_get_first_child(shellHandle));
 			int[] headerNaturalHeight = new int[1];
-			GTK4.gtk_widget_measure(header, GTK.GTK_ORIENTATION_VERTICAL, 0, null, headerNaturalHeight, null, null);
+			GTK4.gtk_widget_measure(header, GTK.GTK_ORIENTATION_VERTICAL, -1, null, headerNaturalHeight, null, null);
 			widthA[0] = monitorSize.width;
 			heightA[0] = monitorSize.height - headerNaturalHeight[0];
 		}
@@ -2377,7 +2377,7 @@ int setBounds (int x, int y, int width, int height, boolean move, boolean resize
 				 */
 				long header = GTK4.gtk_widget_get_next_sibling(GTK4.gtk_widget_get_first_child(shellHandle));
 				int[] headerNaturalHeight = new int[1];
-				GTK4.gtk_widget_measure(header, GTK.GTK_ORIENTATION_VERTICAL, 0, null, headerNaturalHeight, null, null);
+				GTK4.gtk_widget_measure(header, GTK.GTK_ORIENTATION_VERTICAL, -1, null, headerNaturalHeight, null, null);
 				GTK.gtk_window_set_default_size(shellHandle, width, height + headerNaturalHeight[0]);
 			} else {
 				GTK3.gtk_window_resize (shellHandle, width, height);
@@ -2544,7 +2544,7 @@ void setInitialBounds() {
 				long header = GTK4.gtk_window_get_titlebar(shellHandle);
 				int[] headerNaturalHeight = new int[1];
 				if (header != 0) {
-					GTK4.gtk_widget_measure(header, GTK.GTK_ORIENTATION_VERTICAL, 0, null, headerNaturalHeight, null, null);
+					GTK4.gtk_widget_measure(header, GTK.GTK_ORIENTATION_VERTICAL, -1, null, headerNaturalHeight, null, null);
 				}
 
 				GTK.gtk_window_set_default_size(shellHandle, width, height + headerNaturalHeight[0]);