message: Simplify watch only balance display logic
  Instead of making the watch-only balances independent, make them inherit
  their visible state from non watch-only balances. This prevents the
  situation where a watch-only line item is blank.
diff: @@ -281,28 +281,28 @@ void OverviewPage::setBalance(const CAmount& balance, const CAmount& unconfirmed
  // PIV Available
  bool showPIVAvailable = settingShowAllBalances || pivAvailableBalance != nTotalBalance;
  - bool showWatchOnlyPIVAvailable = settingShowAllBalances || nAvailableWatchBalance != nTotalWatchBalance;
  + bool showWatchOnlyPIVAvailable = showPIVAvailable || nAvailableWatchBalance != nTotalWatchBalance;
  ui->labelBalanceText->setVisible(showPIVAvailable || showWatchOnlyPIVAvailable);
  ui->labelBalance->setVisible(showPIVAvailable || showWatchOnlyPIVAvailable);
  ui->labelWatchAvailable->setVisible(showWatchOnlyPIVAvailable && showWatchOnly);
  // PIV Pending
  bool showPIVPending = settingShowAllBalances || unconfirmedBalance != 0;
  - bool showWatchOnlyPIVPending = settingShowAllBalances || watchUnconfBalance != 0;
  + bool showWatchOnlyPIVPending = showPIVPending || watchUnconfBalance != 0;
  ui->labelPendingText->setVisible(showPIVPending || showWatchOnlyPIVPending);
  ui->labelUnconfirmed->setVisible(showPIVPending || showWatchOnlyPIVPending);
  ui->labelWatchPending->setVisible(showWatchOnlyPIVPending && showWatchOnly);
  // PIV Immature
  bool showPIVImmature = settingShowAllBalances || immatureBalance != 0;
  - bool showWatchOnlyImmature = settingShowAllBalances || watchImmatureBalance != 0;
  + bool showWatchOnlyImmature = showPIVImmature || watchImmatureBalance != 0;
  ui->labelImmatureText->setVisible(showPIVImmature || showWatchOnlyImmature);
  ui->labelImmature->setVisible(showPIVImmature || showWatchOnlyImmature); // for symmetry reasons also show immature label when the watch-only one is shown
  ui->labelWatchImmature->setVisible(showWatchOnlyImmature && showWatchOnly); // show watch-only immature balance
  // PIV Locked
  bool showPIVLocked = settingShowAllBalances || nLockedBalance != 0;
  - bool showWatchOnlyPIVLocked = settingShowAllBalances || nWatchOnlyLockedBalance != 0;
  + bool showWatchOnlyPIVLocked = showPIVLocked || nWatchOnlyLockedBalance != 0;
  ui->labelLockedBalanceText->setVisible(showPIVLocked || showWatchOnlyPIVLocked);
  ui->labelLockedBalance->setVisible(showPIVLocked || showWatchOnlyPIVLocked);
  ui->labelWatchLocked->setVisible(showWatchOnlyPIVLocked && showWatchOnly);
  