Remove function menu from wxGTK mathtext example

GTK no longer defaults to showing images in menus, unless they are set
to important. However, wx does not appear to expose that setting, so it
just produces a menu of blank options.

Author: QuLogic

examples/user_interfaces/mathtext_wx_sgskip.py

@@ -15,7 +15,6 @@
 import numpy as np
 import wx
 
-IS_GTK = 'wxGTK' in wx.PlatformInfo
 IS_WIN = 'wxMSW' in wx.PlatformInfo
 
 
@@ -66,7 +65,7 @@ def __init__(self, parent, title):
         menuBar.Append(menu, "&File")
         self.Bind(wx.EVT_MENU, self.OnClose, m_exit)
 
-        if IS_GTK or IS_WIN:
+        if IS_WIN:
             # Equation Menu
             menu = wx.Menu()
             for i, (mt, func) in enumerate(functions):