[library-web] Add an error when html5lib can't be imported

[William Jon McCann <mccann src gnome org>]

commit aa0d2422cf81b1d0a106a5af080164d0e0531808
Author: William Jon McCann <william jon mccann gmail com>
Date:   Tue Feb 18 15:38:07 2014 -0500

    Add an error when html5lib can't be imported
    
    It means we can't tranform the shipped documentation.

 src/modtypes/gtkdoc.py    |    1 +
 src/modtypes/htmlfiles.py |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/modtypes/gtkdoc.py b/src/modtypes/gtkdoc.py
index a9cfa78..31be29d 100644
--- a/src/modtypes/gtkdoc.py
+++ b/src/modtypes/gtkdoc.py
@@ -113,6 +113,7 @@ class GtkDocModule(DocModule):
                     try:
                         import html5lib
                     except ImportError:
+                        logging.error('missing html5lib, unable to convert %s' % doc_module)
                         html5lib = None
                     if html5lib:
                         # convert files to XML, then process them with xsltproc
diff --git a/src/modtypes/htmlfiles.py b/src/modtypes/htmlfiles.py
index 605ac9a..8cc5925 100644
--- a/src/modtypes/htmlfiles.py
+++ b/src/modtypes/htmlfiles.py
@@ -75,6 +75,7 @@ class HtmlFilesModule(DocModule):
             try:
                 import html5lib
             except ImportError:
+                logging.error('missing html5lib, unable to convert %s' % doc_module)
                 html5lib = None
 
             if html5lib: