fix(gui): handle null value in TableCellRenderer (#1642)

jadx-gui/src/main/java/jadx/gui/ui/dialog/CommonSearchDialog.java

@@ -420,6 +420,9 @@ public abstract class CommonSearchDialog extends JFrame {
 		@Override
 		public Component getTableCellRendererComponent(JTable table, Object obj,
 				boolean isSelected, boolean hasFocus, int row, int column) {
+			if (obj == null || table == null) {
+				return emptyLabel;
+			}
 			Component comp = makeCell((JNode) obj, column);
 			updateSelection(table, comp, column, isSelected);
 			return comp;

jadx-gui/src/main/java/jadx/gui/ui/dialog/SearchDialog.java

@@ -553,6 +553,7 @@ public class SearchDialog extends CommonSearchDialog {
 	}
 
 	private void addSearchResult(JNode node) {
+		Objects.requireNonNull(node);
 		synchronized (pendingResults) {
 			UiUtils.notUiThreadGuard();
 			pendingResults.add(node);