Do not accept on hotkey syntax errors

Previously you could type whatever gibberish you wanted into the formula bar, press OK, and receive a modal syntax error window. Closing the syntax error window would cause the hotkey config window to close as well, and your gibberish would be applied to the hotkey assignment.

This commit requires that a syntax error does not occur before accept() is called.

Source/Core/DolphinQt/Config/Mapping/IOWindow.cpp

@@ -515,9 +515,11 @@ void IOWindow::OnDialogButtonPressed(QAbstractButton* button)
   {
     ModalMessageBox::warning(this, tr("Error"), tr("The expression contains a syntax error."));
   }
-
-  // must be the OK button
-  accept();
+  else
+  {
+    // must be the OK button
+    accept();
+  }
 }
 
 void IOWindow::OnDetectButtonPressed()