Qt: Store Show Packet Bytes settings in recent

Store the Show Packt Bytes "Decode As" and "Show As" settings in
recent.

The options for "Show as" for Show Packet Bytes are a superset of the
"Show data as" for Follow Stream, and they're conceptually doing
the same thing. Use the same enum for both - Follow Stream doesn't
support all these options, but maybe it should in the future.

To do this, we break the strict correspondance between the index
in the respective comboboxes and the value of the enum. Use
findData when setting the current index so that this doesn't matter;
this also keeps us from having to be as strict about keeping new
entries in alphabetical order.

Fix #17796

ui/qt/follow_stream_dialog.cpp

@@ -65,6 +65,8 @@ static QMutex loop_break_mutex;
 // Indicates that a Follow Stream is currently running
 static gboolean isReadRunning;
 
+Q_DECLARE_METATYPE(bytes_show_type)
+
 FollowStreamDialog::FollowStreamDialog(QWidget &parent, CaptureFile &cf, int proto_id) :
     WiresharkDialog(parent, cf),
     ui(new Ui::FollowStreamDialog),
@@ -111,7 +113,7 @@ FollowStreamDialog::FollowStreamDialog(QWidget &parent, CaptureFile &cf, int pro
     // UTF-8 is guaranteed to exist as a QTextCodec
     cbcs->addItem(tr("UTF-8"), SHOW_CODEC);
     cbcs->addItem(tr("YAML"), SHOW_YAML);
-    cbcs->setCurrentIndex(static_cast<int>(recent.gui_follow_show));
+    cbcs->setCurrentIndex(cbcs->findData(recent.gui_follow_show));
     cbcs->blockSignals(false);
 
     b_filter_out_ = ui->buttonBox->addButton(tr("Filter Out This Stream"), QDialogButtonBox::ActionRole);
@@ -359,7 +361,7 @@ void FollowStreamDialog::on_cbDirections_currentIndexChanged(int idx)
 void FollowStreamDialog::on_cbCharset_currentIndexChanged(int idx)
 {
     if (idx < 0) return;
-    recent.gui_follow_show = static_cast<follow_show_type>(ui->cbCharset->itemData(idx).toInt());
+    recent.gui_follow_show = ui->cbCharset->currentData().value<bytes_show_type>();
     readStream();
 }
 
@@ -901,6 +903,12 @@ DIAG_ON(stringop-overread)
         addText(ba, is_from_server, packet_num);
         break;
     }
+
+    default:
+        /* The other Show types are supported in Show Packet Bytes but
+         * not here in Follow. (XXX: Maybe some could be added?)
+         */
+        ws_assert_not_reached();
     }
 
     if (last_packet_ == 0) {