Lets help/menu tree item double-clicking run commands. Backported from develbranch_6

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@39929 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/wxgui.py

@@ -453,9 +453,10 @@ class GMFrame(wx.Frame):
 
         return cmdlist
 
-    def RunMenuCmd(self, event):
+    def RunMenuCmd(self, event, cmd = ''):
         """!Run command selected from menu"""
-        cmd = self.GetMenuCmd(event)
+        if event:
+            cmd = self.GetMenuCmd(event)
         self.goutput.RunCmd(cmd, switchPage=True)
 
     def OnMenuCmd(self, event, cmd = ''):