[GTK] Add native methods for retrieving icons based on size and scale factor

This change adds the native method gtk_icon_theme_lookup_by_gicon_for_scale() and
gdk_window_get_scale_factor(), to prepare for retrieving theme application icons based on DPI.

See: #3003

Author: trancexpress

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/gtk3.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2025 IBM Corporation and others.
+ * Copyright (c) 2000, 2026 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -1097,6 +1097,18 @@ JNIEXPORT jlong JNICALL GTK3_NATIVE(gtk_1icon_1theme_1lookup_1by_1gicon)
 }
 #endif
 
+#ifndef NO_gtk_1icon_1theme_1lookup_1by_1gicon_1for_1scale
+JNIEXPORT jlong JNICALL GTK3_NATIVE(gtk_1icon_1theme_1lookup_1by_1gicon_1for_1scale)
+	(JNIEnv *env, jclass that, jlong arg0, jlong arg1, jint arg2, jint arg3, jint arg4)
+{
+	jlong rc = 0;
+	GTK3_NATIVE_ENTER(env, that, gtk_1icon_1theme_1lookup_1by_1gicon_1for_1scale_FUNC);
+	rc = (jlong)gtk_icon_theme_lookup_by_gicon_for_scale((GtkIconTheme *)arg0, (GIcon *)arg1, (gint)arg2, (gint)arg3, (GtkIconLookupFlags)arg4);
+	GTK3_NATIVE_EXIT(env, that, gtk_1icon_1theme_1lookup_1by_1gicon_1for_1scale_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO_gtk_1im_1context_1filter_1keypress
 JNIEXPORT jboolean JNICALL GTK3_NATIVE(gtk_1im_1context_1filter_1keypress)
 	(JNIEnv *env, jclass that, jlong arg0, jlong arg1)

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/gtk3_stats.h

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2025 IBM Corporation and others.
+ * Copyright (c) 2000, 2026 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -111,6 +111,7 @@ typedef enum {
 	gtk_1icon_1theme_1get_1default_FUNC,
 	gtk_1icon_1theme_1load_1icon_FUNC,
 	gtk_1icon_1theme_1lookup_1by_1gicon_FUNC,
+	gtk_1icon_1theme_1lookup_1by_1gicon_1for_1scale_FUNC,
 	gtk_1im_1context_1filter_1keypress_FUNC,
 	gtk_1image_1new_1from_1icon_1name_FUNC,
 	gtk_1image_1new_1from_1surface_FUNC,

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2025 IBM Corporation and others. All rights reserved.
+ * Copyright (c) 2000, 2026 IBM Corporation and others. All rights reserved.
  * The contents of this file are made available under the terms
  * of the GNU Lesser General Public License (LGPL) Version 2.1 that
  * accompanies this distribution (lgpl-v21.txt).  The LGPL is also
@@ -2755,6 +2755,18 @@ JNIEXPORT void JNICALL GDK_NATIVE(gdk_1window_1get_1root_1origin)
 }
 #endif
 
+#ifndef NO_gdk_1window_1get_1scale_1factor
+JNIEXPORT jint JNICALL GDK_NATIVE(gdk_1window_1get_1scale_1factor)
+	(JNIEnv *env, jclass that, jlong arg0)
+{
+	jint rc = 0;
+	GDK_NATIVE_ENTER(env, that, gdk_1window_1get_1scale_1factor_FUNC);
+	rc = (jint)gdk_window_get_scale_factor((GdkWindow *)arg0);
+	GDK_NATIVE_EXIT(env, that, gdk_1window_1get_1scale_1factor_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO_gdk_1window_1get_1state
 JNIEXPORT jint JNICALL GDK_NATIVE(gdk_1window_1get_1state)
 	(JNIEnv *env, jclass that, jlong arg0)

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.h

@@ -194,6 +194,7 @@
 #define NO_gdk_1window_1get_1root_1origin
 #define NO_gdk_1window_1get_1state
 #define NO_gdk_1window_1get_1user_1data
+#define NO_gdk_1window_1get_1scale_1factor
 #define NO_gdk_1window_1get_1visible_1region
 #define NO_gdk_1window_1show
 #define NO_gdk_1window_1hide

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2025 IBM Corporation and others. All rights reserved.
+ * Copyright (c) 2000, 2026 IBM Corporation and others. All rights reserved.
  * The contents of this file are made available under the terms
  * of the GNU Lesser General Public License (LGPL) Version 2.1 that
  * accompanies this distribution (lgpl-v21.txt).  The LGPL is also
@@ -204,6 +204,7 @@ typedef enum {
 	gdk_1window_1get_1origin_FUNC,
 	gdk_1window_1get_1parent_FUNC,
 	gdk_1window_1get_1root_1origin_FUNC,
+	gdk_1window_1get_1scale_1factor_FUNC,
 	gdk_1window_1get_1state_FUNC,
 	gdk_1window_1get_1user_1data_FUNC,
 	gdk_1window_1get_1visible_1region_FUNC,

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GDK.java

@@ -1107,6 +1107,11 @@ public class GDK extends OS {
 	 */
 	/* [GTK3 only, if-def'd in os.h] */
 	public static final native void gdk_window_get_user_data(long window, long [] data);
+	/**
+	 * @param window cast=(GdkWindow *)
+	 */
+	/* [GTK3 only, if-def'd in os.h] */
+	public static final native int gdk_window_get_scale_factor(long window);
 	/** @param window cast=(GdkWindow *) */
 	/* [GTK3 only, if-def'd in os.h] */
 	public static final native void gdk_window_hide(long window);

bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk3/GTK3.java

@@ -795,6 +795,15 @@ public class GTK3 {
 	 * @param flags cast=(GtkIconLookupFlags)
 	 */
 	public static final native long gtk_icon_theme_lookup_by_gicon(long icon_theme, long icon, int size, int flags);
+	/* GtkIconTheme */
+	/**
+	 * @param icon_theme cast=(GtkIconTheme *)
+	 * @param icon cast=(GIcon *)
+	 * @param size cast=(gint)
+	 * @param scale cast=(gint)
+	 * @param flags cast=(GtkIconLookupFlags)
+	 */
+	public static final native long gtk_icon_theme_lookup_by_gicon_for_scale(long icon_theme, long icon, int size, int scale, int flags);
 	/**
 	 * @param icon_theme cast=(GtkIconTheme *)
 	 * @param icon_name cast=(const gchar *)