MatrixRTC: Disable room transport fallback for keys (#4929)

* matrixRTC: Disable room transport fallback for keys

* post rebase fix

* post merge fix

---------

Co-authored-by: Will Hunt <will@half-shot.uk>

src/matrixrtc/EncryptionManager.ts

@@ -7,11 +7,6 @@ import { type CallMembership } from "./CallMembership.ts";
 import { type KeyTransportEventListener, KeyTransportEvents, type IKeyTransport } from "./IKeyTransport.ts";
 import { isMyMembership, type ParticipantId, type Statistics } from "./types.ts";
 import { getParticipantId } from "./utils.ts";
-import {
-    type EnabledTransports,
-    RoomAndToDeviceEvents,
-    RoomAndToDeviceTransport,
-} from "./RoomAndToDeviceKeyTransport.ts";
 
 /**
  * This interface is for testing and for making it possible to interchange the encryption manager.
@@ -119,10 +114,7 @@ export class EncryptionManager implements IEncryptionManager {
         this.manageMediaKeys = this.joinConfig?.manageMediaKeys ?? this.manageMediaKeys;
 
         this.transport.on(KeyTransportEvents.ReceivedKeys, this.onNewKeyReceived);
-        // Deprecate RoomKeyTransport: this can get removed.
-        if (this.transport instanceof RoomAndToDeviceTransport) {
-            this.transport.on(RoomAndToDeviceEvents.EnabledTransportsChanged, this.onTransportChanged);
-        }
+
         this.transport.start();
         if (this.joinConfig?.manageMediaKeys) {
             this.makeNewSenderKey();
@@ -315,10 +307,6 @@ export class EncryptionManager implements IEncryptionManager {
         }
     };
 
-    private onTransportChanged: (enabled: EnabledTransports) => void = () => {
-        this.requestSendCurrentKey();
-    };
-
     public onNewKeyReceived: KeyTransportEventListener = (userId, deviceId, keyBase64Encoded, index, timestamp) => {
         this.logger.debug(`Received key over key transport ${userId}:${deviceId} at index ${index}`);
         this.setEncryptionKey(userId, deviceId, index, keyBase64Encoded, timestamp);