Object API changes so these functions now require a scene as first argument:

create_mesh, create_dupli_list, make_display_list and is_visible.

This is done in order to make these context independent as the RNA API should
be as much as possible, and to fix #21297 and #21719, where there was an
assumption from these functions that there is a scene in the context, which
does not work for external render engines exporting in a separate thread.

Also avoided using context in a number of other functions, ideally only UI/WM
type functions should use context.

I've updated the scripts in trunk, but the addons and external ones in
development will need updates too.

release/scripts/io/export_mdd.py

@@ -84,7 +84,7 @@ def write(filename, sce, ob, PREF_STARTFRAME, PREF_ENDFRAME, PREF_FPS):
 
     orig_frame = sce.frame_current
     sce.set_frame(PREF_STARTFRAME)
-    me = ob.create_mesh(True, 'PREVIEW')
+    me = ob.create_mesh(sce, True, 'PREVIEW')
 
     #Flip y and z
     mat_flip = Mathutils.Matrix(\
@@ -123,7 +123,7 @@ def write(filename, sce, ob, PREF_STARTFRAME, PREF_ENDFRAME, PREF_FPS):
         """
 
         sce.set_frame(frame)
-        me = ob.create_mesh(True, 'PREVIEW')
+        me = ob.create_mesh(sce, True, 'PREVIEW')
         check_vertcount(me, numverts)
         me.transform(mat_flip * ob.matrix)