Add loading of user template functions to the new backend

src/calibre/db/__init__.py

@@ -168,8 +168,7 @@ How this will proceed:
     work.
 
 Various things that require other things before they can be migrated:
-    1. From initialize_dynamic(): set_saved_searches,
-                    load_user_template_functions. Also add custom
+    1. From initialize_dynamic(): Also add custom
                     columns/categories/searches info into
                     self.field_metadata.
     2. Catching DatabaseException and sqlite.Error when creating new

src/calibre/db/backend.py

@@ -29,6 +29,7 @@ from calibre.utils.filenames import (is_case_sensitive, samefile, hardlink_file,
                                      WindowsAtomicFolderMove)
 from calibre.utils.magick.draw import save_cover_data_to
 from calibre.utils.recycle_bin import delete_tree, delete_file
+from calibre.utils.formatter_functions import load_user_template_functions
 from calibre.db.tables import (OneToOneTable, ManyToOneTable, ManyToManyTable,
         SizeTable, FormatsTable, AuthorsTable, IdentifiersTable, PathTable,
         CompositeTable, UUIDTable)
@@ -372,6 +373,8 @@ class DB(object):
         self.initialize_prefs(default_prefs, restore_all_prefs, progress_callback)
         self.initialize_custom_columns()
         self.initialize_tables()
+        load_user_template_functions(self.library_id,
+                                        self.prefs.get('user_template_functions', []))
 
     def initialize_prefs(self, default_prefs, restore_all_prefs, progress_callback):  # {{{
         self.prefs = DBPrefs(self)

src/calibre/db/legacy.py

@@ -55,7 +55,7 @@ class LibraryDatabase(object):
             default_prefs=None, read_only=False, is_second_db=False,
             progress_callback=lambda x, y:True, restore_all_prefs=False):
 
-        self.is_second_db = is_second_db  # TODO: Use is_second_db
+        self.is_second_db = is_second_db
         self.listeners = set()
 
         backend = self.backend = DB(library_path, default_prefs=default_prefs,