RoomView: guard against unmounting during peeking
RoomView: guard against unmounting during peeking

it's possible for the user to change room before the peek operation completes. Check if we've been unmounted before setting state.
matrix-org/matrix-react-sdk,aperezdc/matrix-react-sdk,aperezdc/matrix-react-sdk,aperezdc/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,aperezdc/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk