resize tray icon because a 1024x1024 icon won't show in ubuntu (bug)

src/qt/bitcoingui.cpp

@@ -115,8 +115,8 @@ BitcoinGUI::BitcoinGUI(const NetworkStyle *networkStyle, QWidget *parent) :
     }
     windowTitle += " " + networkStyle->getTitleAddText();
 #ifndef Q_OS_MAC
-    QApplication::setWindowIcon(networkStyle->getAppIcon());
-    setWindowIcon(networkStyle->getAppIcon());
+    QApplication::setWindowIcon(networkStyle->getTrayAndWindowIcon());
+    setWindowIcon(networkStyle->getTrayAndWindowIcon());
 #else
     MacDockIconHandler::instance()->setIcon(networkStyle->getAppIcon());
 #endif
@@ -491,7 +491,7 @@ void BitcoinGUI::createTrayIcon(const NetworkStyle *networkStyle)
     trayIcon = new QSystemTrayIcon(this);
     QString toolTip = tr("Bitcoin Core client") + " " + networkStyle->getTitleAddText();
     trayIcon->setToolTip(toolTip);
-    trayIcon->setIcon(networkStyle->getAppIcon());
+    trayIcon->setIcon(networkStyle->getTrayAndWindowIcon());
     trayIcon->show();
 #endif
 

src/qt/networkstyle.cpp

@@ -72,6 +72,7 @@ NetworkStyle::NetworkStyle(const QString &appName, const int iconColorHueShift,
     }
 
     appIcon             = QIcon(pixmap);
+    trayAndWindowIcon   = QIcon(pixmap.scaled(QSize(256,256)));
 }
 
 const NetworkStyle *NetworkStyle::instantiate(const QString &networkId)

src/qt/networkstyle.h

@@ -18,6 +18,7 @@ public:
 
     const QString &getAppName() const { return appName; }
     const QIcon &getAppIcon() const { return appIcon; }
+    const QIcon &getTrayAndWindowIcon() const { return trayAndWindowIcon; }
     const QString &getTitleAddText() const { return titleAddText; }
 
 private:
@@ -25,6 +26,7 @@ private:
 
     QString appName;
     QIcon appIcon;
+    QIcon trayAndWindowIcon;
     QString titleAddText;
 };