Fixed problem with incorrect panel background on OS X.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@31661 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

wxPython/wx/lib/filebrowsebutton.py

@@ -90,6 +90,9 @@ class FileBrowseButton(wx.Panel):
 
         # try to set the background colour
         try:
+            #Question: is this still needed on other platforms?
+            #It should have transparent background on Mac
+            if wx.Platform != "__WXMAC__":
                 self.SetBackgroundColour(self._bc)
         except:
             pass