[library-web/responsive] ignore $(NULL) pages

[Frederic Peters <fpeters src gnome org>]

commit ec42e08f3864869f693e988d647083683f8f0405
Author: FrÃdÃric PÃters <fpeters 0d be>
Date:   Fri Feb 1 14:01:32 2013 +0100

    ignore $(NULL) pages

 src/modtypes/mallard.py |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/modtypes/mallard.py b/src/modtypes/mallard.py
index 1d927e1..1dbf58b 100644
--- a/src/modtypes/mallard.py
+++ b/src/modtypes/mallard.py
@@ -215,6 +215,9 @@ class MallardModule(DocModule):
         except IndexError:
             return
 
+        if '$(NULL)' in doc_pages: # common idiom
+            doc_pages.remove('$(NULL)')
+
         try:
             doc_figures = re.findall(r'(?:DOC_FIGURES|HELP_FIGURES|HELP_MEDIA)\s+=\s+(.*)',
                     self.makefile_am)[0].split()