message: Normalise cancel behaviour for room avatar
  This normalises the behaviour of the "Cancel" button for the room profile so
  that it _always_ restores the existing value for all of room name, topic, and
  avatar, instead of performing a mix of restore and remove.
  Fixes
diff: @@ -69,22 +69,23 @@ export default class RoomProfileSettings extends React.Component {
  // clear file upload field so same file can be selected
  this._avatarUpload.current.value = "";
  this.setState({
  - avatarUrl: undefined,
  - avatarFile: undefined,
  + avatarUrl: null,
  + avatarFile: null,
  enableProfileSave: true,
  });
  };
  - _clearProfile = async (e) => {
  + _cancelProfileChanges = async (e) => {
  e.stopPropagation();
  e.preventDefault();
  if (!this.state.enableProfileSave) return;
  - this._removeAvatar();
  this.setState({
  enableProfileSave: false,
  displayName: this.state.originalDisplayName,
  topic: this.state.originalTopic,
  + avatarUrl: this.state.originalAvatarUrl,
  + avatarFile: null,
  });
  };
  @@ -112,7 +113,7 @@ export default class RoomProfileSettings extends React.Component {
  newState.originalAvatarUrl = newState.avatarUrl;
  newState.avatarFile = null;
  } else if (this.state.originalAvatarUrl !== this.state.avatarUrl) {
  - await client.sendStateEvent(this.props.roomId, 'm.room.avatar', {url: undefined}, '');
  + await client.sendStateEvent(this.props.roomId, 'm.room.avatar', {}, '');
  }
  if (this.state.originalTopic !== this.state.topic) {
  @@ -168,11 +169,15 @@ export default class RoomProfileSettings extends React.Component {
  const AvatarSetting = sdk.getComponent('settings.AvatarSetting');
  let profileSettingsButtons;
  - if (this.state.canSetTopic || this.state.canSetName) {
  + if (
  + this.state.canSetName ||
  + this.state.canSetTopic ||
  + this.state.canSetAvatar
  + ) {
  profileSettingsButtons = (
  <div className="mx_ProfileSettings_buttons">
  <AccessibleButton
  - onClick={this._clearProfile}
  + onClick={this._cancelProfileChanges}
  kind="link"
  disabled={!this.state.enableProfileSave}
  >
  