vout: attach picture heap to temporary picture, so that modules (such as...

vout: attach picture heap to temporary picture, so that modules (such as blend) have access to the extra info in heap

src/video_output/vout_pictures.c

@@ -376,6 +376,8 @@ picture_t * vout_RenderPicture( vout_thread_t *p_vout, picture_t *p_pic,
                                   p_vout->fmt_out.i_aspect );
             p_tmp_pic->i_type = MEMORY_PICTURE;
             p_tmp_pic->i_status = RESERVED_PICTURE;
+            /* some modules (such as blend)  needs to know the extra information in picture heap */
+            p_tmp_pic->p_heap = &p_vout->output;
         }
 
         /* Convert image to the first direct buffer */