Remove colors -> completion.item.bg config option.

This wasn't used anywhere...

doc/help/settings.asciidoc

@@ -166,7 +166,6 @@
 |<<colors-completion.fg,completion.fg>>|Text color of the completion widget.
 |<<colors-completion.bg,completion.bg>>|Background color of the completion widget.
 |<<colors-completion.alternate-bg,completion.alternate-bg>>|Alternating background color of the completion widget.
-|<<colors-completion.item.bg,completion.item.bg>>|Background color of completion widget items.
 |<<colors-completion.category.fg,completion.category.fg>>|Foreground color of completion widget category headers.
 |<<colors-completion.category.bg,completion.category.bg>>|Background color of the completion widget category headers.
 |<<colors-completion.category.border.top,completion.category.border.top>>|Top border color of the completion widget category headers.
@@ -1341,12 +1340,6 @@ Alternating background color of the completion widget.
 
 Default: +pass:[#444444]+
 
-[[colors-completion.item.bg]]
-=== completion.item.bg
-Background color of completion widget items.
-
-Default: +pass:[${completion.bg}]+
-
 [[colors-completion.category.fg]]
 === completion.category.fg
 Foreground color of completion widget category headers.

qutebrowser/config/config.py

@@ -264,6 +264,7 @@ class ConfigManager(QObject):
     DELETED_OPTIONS = [
         ('colors', 'tab.seperator'),
         ('colors', 'tabs.seperator'),
+        ('colors', 'completion.item.bg'),
     ]
 
     changed = pyqtSignal(str, str)

qutebrowser/config/configdata.py

@@ -683,10 +683,6 @@ DATA = collections.OrderedDict([
          SettingValue(typ.QssColor(), '#444444'),
          "Alternating background color of the completion widget."),
 
-        ('completion.item.bg',
-         SettingValue(typ.QssColor(), '${completion.bg}'),
-         "Background color of completion widget items."),
-
         ('completion.category.fg',
          SettingValue(typ.QtColor(), 'white'),
          "Foreground color of completion widget category headers."),