Merge bitcoin-core/gui#43: bugfix: Call setWalletActionsEnabled(true) only for the first wallet

20c9e03554 gui: Call setWalletActionsEnabled(true) only for the first wallet (Hennadii Stepanov)

Pull request description:

  On master (a78742830a) there is a bug:
  - open an encrypted wallet; please note that the "Encrypt Wallet..." menu item is disabled that is expected:
  ![Screenshot from 2020-08-03 12-38-37](https://user-images.githubusercontent.com/32963518/89169084-70060c80-d586-11ea-86b9-05ef38d08f41.png)
  - then open any other wallet; note that the "Encrypt Wallet..." menu item gets enabled that is wrong:
  ![Screenshot from 2020-08-03 12-42-36](https://user-images.githubusercontent.com/32963518/89169385-d68b2a80-d586-11ea-9813-a533a847e098.png)

  This PR fixes this bug.

ACKs for top commit:
  jonasschnelli:
    Tested ACK 20c9e03554 - I could reproduce the issue on master and have verify that this PR fixes it.
  achow101:
    ACK 20c9e03554

Tree-SHA512: 2c9ab94bde8c4f413b0a95c05bf3a1a29f5910e0f99d6639a11dd77758c78af25b060b3fecd78117066ef15b113feb79870bc1347cc04289da915c00623e5787

src/qt/bitcoingui.cpp

@@ -669,14 +669,15 @@ void BitcoinGUI::addWallet(WalletModel* walletModel)
 {
     if (!walletFrame) return;
     if (!walletFrame->addWallet(walletModel)) return;
-    const QString display_name = walletModel->getDisplayName();
-    setWalletActionsEnabled(true);
     rpcConsole->addWallet(walletModel);
-    m_wallet_selector->addItem(display_name, QVariant::fromValue(walletModel));
-    if (m_wallet_selector->count() == 2) {
+    if (m_wallet_selector->count() == 0) {
+        setWalletActionsEnabled(true);
+    } else if (m_wallet_selector->count() == 1) {
         m_wallet_selector_label_action->setVisible(true);
         m_wallet_selector_action->setVisible(true);
     }
+    const QString display_name = walletModel->getDisplayName();
+    m_wallet_selector->addItem(display_name, QVariant::fromValue(walletModel));
 }
 
 void BitcoinGUI::removeWallet(WalletModel* walletModel)