message: qt, refactor: Drop redundant checks of walletModel
  The walletModel member is set in the WalletView constructor now.
diff: @@ -132,7 +132,7 @@ void WalletView::setClientModel(ClientModel *_clientModel)
  overviewPage->setClientModel(_clientModel);
  sendCoinsPage->setClientModel(_clientModel);
  - if (walletModel) walletModel->setClientModel(_clientModel);
  + walletModel->setClientModel(_clientModel);
  }
  mintingView->setModel(_walletModel);
  @@ -141,8 +141,9 @@ void WalletView::setClientModel(ClientModel *_clientModel)
  void WalletView::processNewTransaction(const QModelIndex& parent, int start, int /*end*/)
  {
  // Prevent balloon-spam when initial block download is in progress
  - if (!walletModel || !clientModel || clientModel->node().isInitialBlockDownload())
  + if (!clientModel || clientModel->node().isInitialBlockDownload()) {
  return;
  + }
  TransactionTableModel *ttm = walletModel->getTransactionTableModel();
  if (!ttm || ttm->processingQueuedTransactions())
  @@ -222,8 +223,6 @@ void WalletView::showOutOfSyncWarning(bool fShow)
  void WalletView::encryptWallet()
  {
  - if(!walletModel)
  - return;
  AskPassphraseDialog dlg(AskPassphraseDialog::Encrypt, this);
  dlg.setModel(walletModel);
  dlg.exec();
  @@ -291,8 +290,6 @@ void WalletView::changePassphrase()
  void WalletView::unlockWallet()
  {
  - if(!walletModel)
  - return;
  // Unlock wallet when requested by wallet model
  if (walletModel->getEncryptionStatus() == WalletModel::Locked)
  {
  @@ -304,17 +301,11 @@ void WalletView::unlockWallet()
  void WalletView::usedSendingAddresses()
  {
  - if(!walletModel)
  - return;
  -
  GUIUtil::bringToFront(usedSendingAddressesPage);
  }
  void WalletView::usedReceivingAddresses()
  {
  - if(!walletModel)
  - return;
  -
  GUIUtil::bringToFront(usedReceivingAddressesPage);
  }
  