Fixed bug of #2379 pullrequestreview-254461303

Fixed bug of #2379 pullrequestreview-254461303
Redundant paintings when user move mouse on the icon, pixel by pixel.

shadowsocks-csharp/View/MenuViewController.cs

@@ -86,7 +86,6 @@ namespace Shadowsocks.View
             _notifyIcon.MouseClick += notifyIcon1_Click;
             _notifyIcon.MouseDoubleClick += notifyIcon1_DoubleClick;
             _notifyIcon.BalloonTipClosed += _notifyIcon_BalloonTipClosed;
-            _notifyIcon.MouseMove += _notifyIcon_MouseMove;
             controller.TrafficChanged += controller_TrafficChanged;
 
             this.updateChecker = new UpdateChecker();
@@ -108,11 +107,6 @@ namespace Shadowsocks.View
             }
         }
 
-        private void _notifyIcon_MouseMove(object sender, MouseEventArgs e)
-        {
-            UpdateTrayIcon();
-        }
-
         private void controller_TrafficChanged(object sender, EventArgs e)
         {
             if (icon_baseBitmap == null)
@@ -632,6 +626,7 @@ namespace Shadowsocks.View
 
         private void notifyIcon1_Click(object sender, MouseEventArgs e)
         {
+            UpdateTrayIcon();
             if (e.Button == MouseButtons.Middle)
             {
                 ShowLogForm();