Change Signature: Fix receiver removal in the dialog

idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/JetFunctionParameterTableModel.java

@@ -39,6 +39,14 @@ public class JetFunctionParameterTableModel extends JetCallableParameterTableMod
               new ReceiverColumn(context.getProject(), methodDescriptor));
     }
 
+    @Override
+    public void removeRow(int idx) {
+        if (getRowValue(idx).parameter == getReceiver()) {
+            setReceiver(null);
+        }
+        super.removeRow(idx);
+    }
+
     @Override
     @Nullable
     public JetParameterInfo getReceiver() {