naughty: Use same object when the remote source request a replacement

Previously, it would create a new object. The leaves the old
`replaces_id` logic mostly intact for now to keep the full backward
compatibility. I don't think anybody would have noticed the changed, by
time and time again we had proof that some silent users have some
amazing and advanced code hidden somewhere. It could be cleaned later
when breaking compatibility isn't an issue.

lib/naughty/dbus.lua

@@ -73,6 +73,9 @@ local function sendNotificationClosed(notificationId, reason)
     end
 end
 
+-- This allow notification to be upadated later.
+local counter = 1
+
 local function convert_icon(w, h, rowstride, channels, data)
     -- Do the arguments look sane? (e.g. we have enough data)
     local expected_length = rowstride * (h - 1) + w * channels
@@ -201,10 +204,24 @@ capi.dbus.connect_signal("org.freedesktop.Notifications",
                     args.timeout = expire / 1000
                 end
                 args.freedesktop_hints = hints
-                notification = nnotif(args)
+
+                -- Try to update existing objects when possible
+                notification = naughty.get_by_id(replaces_id)
+
+                if notification then
+                    for k, v in pairs(args) do
+                        notification[k] = v
+                    end
+                else
+                    counter = counter+1
+                    args.id = counter
+                    notification = nnotif(args)
+                end
+
                 return "u", notification.id
             end
-            return "u", "0"
+            counter = counter+1
+            return "u", counter
         elseif data.member == "CloseNotification" then
             local obj = naughty.get_by_id(appname)
             if obj then

lib/naughty/layout/legacy.lua

@@ -57,10 +57,6 @@ screen.connect_for_each_screen(function(s)
     }
 end)
 
--- Counter for the notifications
--- Required for later access via DBUS
-local counter = 1
-
 --- Evaluate desired position of the notification by index - internal
 --
 -- @param s Screen to use
@@ -342,28 +338,6 @@ function naughty.default_notification_handler(notification, args)
     local opacity = args.opacity or preset.opacity or
         beautiful.notification_opacity
 
-    -- replace notification if needed
-    local reuse_box
-    if args.replaces_id then
-        local obj = naughty.get_by_id(args.replaces_id)
-        if obj then
-            -- destroy this and ...
-            naughty.destroy(obj, naughty.notification_closed_reason.silent, true)
-            reuse_box = obj.box
-        end
-        -- ... may use its ID
-        if args.replaces_id <= counter then
-            notification.id = args.replaces_id
-        else
-            counter = counter + 1
-            notification.id = counter
-        end
-    else
-        -- get a brand new ID
-        counter = counter + 1
-        notification.id = counter
-    end
-
     notification.position = position
 
     -- hook destroy
@@ -515,10 +489,6 @@ function naughty.default_notification_handler(notification, args)
                                shape = shape,
                                type = "notification" })
 
-    if reuse_box then
-        notification.box = reuse_box
-    end
-
     if hover_timeout then notification.box:connect_signal("mouse::enter", hover_destroy) end
 
     notification.size_info = size_info