Add 'keys' to *all* olm messages

(including ones which just carry megolm keys)

lib/crypto/algorithms/olm.js

@@ -119,17 +119,6 @@ OlmEncryption.prototype.encryptMessage = function(room, eventType, content) {
                 room_id: room.roomId,
                 type: eventType,
                 content: content,
-                // Include the ED25519 key so that the recipient knows what
-                // device this message came from.
-                // We don't need to include the curve25519 key since the
-                // recipient will already know this from the olm headers.
-                // When combined with the device keys retrieved from the
-                // homeserver signed by the ed25519 key this proves that
-                // the curve25519 key and the ed25519 key are owned by
-                // the same device.
-                keys: {
-                    "ed25519": self._olmDevice.deviceEd25519Key
-                },
             }
         );
     });