screen: Set the managed flag when creating screens in awful.screen.

lib/awful/screen.lua

@@ -941,10 +941,10 @@ capi.screen.connect_signal("added", function(s)
     -- If it was emited from here when screens are created with fake_add,
     -- the Lua code would not have an opportunity to polutate the screen
     -- metadata. Thus, the DPI may be wrong when setting the wallpaper.
-    --if capi.screen.automatic_factory then
+    if s._managed ~= "Lua" then
         s:emit_signal("request::desktop_decoration")
         s:emit_signal("request::wallpaper")
-    --end
+    end
 end)
 
 -- Resize the wallpaper(s)

lib/awful/screen/dpi.lua

@@ -152,13 +152,14 @@ function module.create_screen_handler(viewport)
         geo.x,
         geo.y,
         geo.width,
-        geo.height
+        geo.height,
+        {_managed = true}
     )
 
     update_screen_viewport(s)
 
-    --s:emit_signal("request::desktop_decoration")
-    --s:emit_signal("request::wallpaper")
+    s:emit_signal("request::desktop_decoration")
+    s:emit_signal("request::wallpaper")
 end
 
 function module.remove_screen_handler(viewport)