[gtk+] broadway: Make the use of next_texture_id clearer

[Alexander Larsson <alexl src gnome org>]

commit 2cad2c21e60f864f62eed2391161af5c4fd48db9
Author: Alexander Larsson <alexl redhat com>
Date:   Tue Dec 5 15:54:36 2017 +0100

    broadway: Make the use of next_texture_id clearer
    
    It used to actually be pre-incremented, so meant like "one before
    next id".

 gdk/broadway/gdkbroadway-server.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gdk/broadway/gdkbroadway-server.c b/gdk/broadway/gdkbroadway-server.c
index 87c1bb7..548f180 100644
--- a/gdk/broadway/gdkbroadway-server.c
+++ b/gdk/broadway/gdkbroadway-server.c
@@ -65,6 +65,7 @@ static void
 gdk_broadway_server_init (GdkBroadwayServer *server)
 {
   server->next_serial = 1;
+  server->next_texture_id = 1;
 }
 
 static void
@@ -647,7 +648,7 @@ gdk_broadway_server_upload_texture (GdkBroadwayServer *server,
   BroadwayRequestUploadTexture msg;
   PngData data;
 
-  id = ++server->next_texture_id;
+  id = server->next_texture_id++;
 
   data.fd = open_shared_memory ();
   data.size = 0;