Fix GTK4 shell location tests.

We cannot set/determine the location of the shell using Window Handle on
GTK4. So fix the test not to test the set and get location on GTK4.

see eclipse-platform#2498

Author: raghucssit

tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_widgets_Shell.java

@@ -457,6 +457,10 @@ public void test_getImeInputMode() {
 @Override
 @Test
 public void test_getLocation() {
+	//Setting location for Windows is not supported in GTK4
+	if (isGTK4()) {
+		return;
+	}
 	shell.setLocation(10,15);
 	assertEquals(":a:", 10, shell.getLocation().x);
 	assertEquals(":b:", 15, shell.getLocation().y);
@@ -999,4 +1003,27 @@ public void test_Issue450_NoShellActivateOnSetFocus() {
 		}
 	}
 }
+
+@Override
+public void test_setLocationLorg_eclipse_swt_graphics_Point() {
+	//Setting location for Windows is not supported in GTK4
+	if (isGTK4()) {
+		return;
+	}
+	super.test_setLocationLorg_eclipse_swt_graphics_Point();
+}
+
+@Override
+public void test_setLocationII() {
+	//Setting location for Windows is not supported in GTK4
+	if (isGTK4()) {
+		return;
+	}
+	super.test_setLocationII();
+}
+
+public static boolean isGTK4() {
+    String gtkVersion = System.getProperty("org.eclipse.swt.internal.gtk.version", "");
+    return SwtTestUtil.isGTK && gtkVersion.startsWith("4");
+}
 }