Revert "vout: fix picture lock/unlock with private pool"

This mostly reverts commit 6a6c23bf.

include/vlc_picture_pool.h

@@ -179,7 +179,6 @@ VLC_USED;
  */
 VLC_API unsigned picture_pool_GetSize(const picture_pool_t *);
 
-bool picture_pool_NeedsLocking(const picture_pool_t *);
 
 #endif /* VLC_PICTURE_POOL_H */
 

src/misc/picture_pool.c

@@ -208,8 +208,6 @@ error:
 
 picture_pool_t *picture_pool_Reserve(picture_pool_t *master, unsigned count)
 {
-    assert(master->pic_unlock == NULL);
-
     picture_t *picture[count ? count : 1];
     unsigned i;
 
@@ -330,11 +328,6 @@ unsigned picture_pool_GetSize(const picture_pool_t *pool)
     return pool->picture_count;
 }
 
-bool picture_pool_NeedsLocking(const picture_pool_t *pool)
-{
-    return pool->pic_lock != NULL || pool->pic_unlock != NULL;
-}
-
 void picture_pool_Enum(picture_pool_t *pool, void (*cb)(void *, picture_t *),
                        void *opaque)
 {

src/video_output/vout_wrapper.c

@@ -133,8 +133,8 @@ int vout_InitWrapper(vout_thread_t *vout)
     picture_pool_t *display_pool =
         vout_display_Pool(vd, allow_dr ? __MAX(VOUT_MAX_PICTURES,
                                                reserved_picture + decoder_picture) : 3);
-    if (allow_dr && !picture_pool_NeedsLocking(display_pool)
-     && picture_pool_GetSize(display_pool) >= reserved_picture + decoder_picture) {
+    if (allow_dr &&
+        picture_pool_GetSize(display_pool) >= reserved_picture + decoder_picture) {
         sys->dpb_size     = picture_pool_GetSize(display_pool) - reserved_picture;
         sys->decoder_pool = display_pool;
         sys->display_pool = display_pool;