wayland-shm: Remove "mapped"

Summary:
Looks like the recent changes to swap/redraw have fixed a problem with
damage tracking and we no longer need this.

Damage history seems ok without it now.

@fix

Reviewers: zmike, devilhorns

Subscribers: cedric

Differential Revision: https://phab.enlightenment.org/D2876

src/modules/evas/engines/wayland_shm/evas_engine.h

@@ -86,7 +86,6 @@ struct _Shm_Surface
    Shm_Leaf *current;
 
    Eina_Bool alpha : 1;
-   Eina_Bool mapped : 1;
 };
 
 struct _Outbuf

src/modules/evas/engines/wayland_shm/evas_outbuf.c

@@ -261,8 +261,6 @@ _evas_outbuf_swapmode_get(Outbuf *ob)
 
    LOGFN(__FILE__, __LINE__, __FUNCTION__);
 
-   if (!ob->surface->mapped) return MODE_FULL;
-
    for (; i < ob->surface->num_buff; i++)
      {
         n = (ob->surface->num_buff + ob->surface->curr_buff - (i)) % ob->surface->num_buff;

src/modules/evas/engines/wayland_shm/evas_shm.c

@@ -426,7 +426,6 @@ _evas_shm_surface_swap(Shm_Surface *surface)
 
    surface->dx = 0;
    surface->dy = 0;
-   surface->mapped = EINA_TRUE;
 }
 
 void *