message: don't block unsent events from being edited
diff: @@ -46,7 +46,8 @@ export function isContentActionable(mxEvent) {
  }
  export function canEditContent(mxEvent) {
  - return isContentActionable(mxEvent) &&
  + return mxEvent.status !== EventStatus.CANCELLED &&
  + mxEvent.getType() === 'm.room.message' &&
  mxEvent.getOriginalContent().msgtype === "m.text" &&
  mxEvent.getSender() === MatrixClientPeg.get().getUserId();
  }
  