gtk: Don't leak temporary hash table in ConstraintLayout::add_constraints_from_description

Fixes #2119

Author: sdroege

gtk4/src/constraint_layout.rs

@@ -21,15 +21,15 @@ impl ConstraintLayout {
                 Some(glib::ffi::g_str_hash),
                 Some(glib::ffi::g_str_equal),
                 Some(glib::ffi::g_free),
-                Some(glib::ffi::g_free),
+                None,
             );
 
             for (key, widget) in views {
                 let key_ptr: *mut libc::c_char = key.to_glib_full();
                 glib::ffi::g_hash_table_insert(
                     hash_table,
                     key_ptr as *mut _,
-                    widget.to_glib_full() as *mut _,
+                    widget.as_ptr() as *mut _,
                 );
             }
 
@@ -43,6 +43,9 @@ impl ConstraintLayout {
                     hash_table,
                     &mut err,
                 );
+
+                glib::ffi::g_hash_table_unref(hash_table);
+
                 if !err.is_null() {
                     Err(from_glib_full(err))
                 } else {