feat(ffi): Add QrCodeData::to_bytes() to allow generation of a QR code (#5939)

Signed-off-by: Hugh Nimmo-Smith <hughns@element.io>

Author: hughns

bindings/matrix-sdk-ffi/CHANGELOG.md

@@ -8,6 +8,8 @@ All notable changes to this project will be documented in this file.
 
 ### Features
 
+- Add `QrCodeData::to_bytes()` to allow generation of a QR code.
+  ([#5939](https://github.com/matrix-org/matrix-rust-sdk/pull/5939))
 - [**breaking**]: The new Latest Event API replaces the old API.
   `Room::new_latest_event` overwrites the `Room::latest_event` method. See the
   documentation of `matrix_sdk::latest_event` to learn about the new API.

bindings/matrix-sdk-ffi/src/qr_code.rs

@@ -236,6 +236,12 @@ impl QrCodeData {
         Ok(Self { inner: qrcode::QrCodeData::from_bytes(&bytes)? }.into())
     }
 
+    /// Serialize the [`QrCodeData`] into a byte vector for encoding as a QR
+    /// code.
+    pub fn to_bytes(&self) -> Vec<u8> {
+        self.inner.to_bytes()
+    }
+
     /// The server name contained within the scanned QR code data.
     ///
     /// Note: This value is only present when scanning a QR code the belongs to