For Python extensions, set __file__ before executing the module

Previously __file__ was set after executing the module. This meant,
however that it was not available during execution.
This patch moves setting __file__ before the execution.

As __file__ is a string (and not bytes), we remove the encoding.

Change-Id: I63fe34b6f5d30f53aab16627d413c87b9de81992
Reviewed-on: https://gerrit.libreoffice.org/70048
Tested-by: Jenkins
Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>

pyuno/source/loader/pythonloader.py

@@ -100,8 +100,8 @@ class Loader( XImplementationLoader, XServiceInfo, unohelper.Base ):
 
                     # compile and execute the module
                     codeobject = compile( src, encfile(filename), "exec" )
+                    mod.__file__ = filename
                     exec(codeobject, mod.__dict__)
-                    mod.__file__ = encfile(filename)
                     g_loadedComponents[url] = mod
                 return mod
             elif "vnd.openoffice.pymodule" == protocol: