Revert "Performance: Remap multiple items in UI"

This reverts commit 948211679f2a0681421160be0d3b90f507bc0be7.
This commit introduced some regressions in the test suite.
As this change is a core part of blender Bastien and I decided to revert
it as the solution isn't clear and needs more investigation.

The following tests FAILED:
	 62 - blendfile_liblink (SEGFAULT)
	 63 - blendfile_library_overrides (SEGFAULT)

It fails in (id_us_ensure_real)

1 files changed, 34 insertions, 34 deletions

diff --git a/source/blender/editors/space_buttons/space_buttons.c b/source/blender/editors/space_buttons/space_buttons.c
index cf1e7788ff8..007a9105c76 100644
--- a/source/blender/editors/space_buttons/space_buttons.c
+++ b/source/blender/editors/space_buttons/space_buttons.c
@@ -32,7 +32,6 @@
 
 #include "BKE_context.h"
 #include "BKE_gpencil_modifier.h" /* Types for registering panels. */
-#include "BKE_lib_remap.h"
 #include "BKE_modifier.h"
 #include "BKE_screen.h"
 #include "BKE_shader_fx.h"
@@ -861,53 +860,54 @@ static void buttons_area_listener(const wmSpaceTypeListenerParams *params)
   }
 }
 
-static void buttons_id_remap(ScrArea *UNUSED(area),
-                             SpaceLink *slink,
-                             const struct IDRemapper *mappings)
+static void buttons_id_remap(ScrArea *UNUSED(area), SpaceLink *slink, ID *old_id, ID *new_id)
 {
   SpaceProperties *sbuts = (SpaceProperties *)slink;
 
-  if (BKE_id_remapper_apply(mappings, &sbuts->pinid, ID_REMAP_APPLY_DEFAULT) ==
-      ID_REMAP_RESULT_SOURCE_UNASSIGNED) {
-    sbuts->flag &= ~SB_PIN_CONTEXT;
+  if (sbuts->pinid == old_id) {
+    sbuts->pinid = new_id;
+    if (new_id == NULL) {
+      sbuts->flag &= ~SB_PIN_CONTEXT;
+    }
   }
 
   if (sbuts->path) {
     ButsContextPath *path = sbuts->path;
-    for (int i = 0; i < path->len; i++) {
-      switch (BKE_id_remapper_apply(mappings, &path->ptr[i].owner_id, ID_REMAP_APPLY_DEFAULT)) {
-        case ID_REMAP_RESULT_SOURCE_UNASSIGNED: {
-          if (i == 0) {
-            MEM_SAFE_FREE(sbuts->path);
-          }
-          else {
-            memset(&path->ptr[i], 0, sizeof(path->ptr[i]) * (path->len - i));
-            path->len = i;
-          }
-          break;
-        }
-        case ID_REMAP_RESULT_SOURCE_REMAPPED: {
-          RNA_id_pointer_create(path->ptr[i].owner_id, &path->ptr[i]);
-          /* There is no easy way to check/make path downwards valid, just nullify it.
-           * Next redraw will rebuild this anyway. */
-          i++;
-          memset(&path->ptr[i], 0, sizeof(path->ptr[i]) * (path->len - i));
-          path->len = i;
-          break;
-        }
 
-        case ID_REMAP_RESULT_SOURCE_NOT_MAPPABLE:
-        case ID_REMAP_RESULT_SOURCE_UNAVAILABLE: {
-          /* Nothing to do. */
-          break;
-        }
+    int i;
+    for (i = 0; i < path->len; i++) {
+      if (path->ptr[i].owner_id == old_id) {
+        break;
+      }
+    }
+
+    if (i == path->len) {
+      /* pass */
+    }
+    else if (new_id == NULL) {
+      if (i == 0) {
+        MEM_SAFE_FREE(sbuts->path);
+      }
+      else {
+        memset(&path->ptr[i], 0, sizeof(path->ptr[i]) * (path->len - i));
+        path->len = i;
       }
     }
+    else {
+      RNA_id_pointer_create(new_id, &path->ptr[i]);
+      /* There is no easy way to check/make path downwards valid, just nullify it.
+       * Next redraw will rebuild this anyway. */
+      i++;
+      memset(&path->ptr[i], 0, sizeof(path->ptr[i]) * (path->len - i));
+      path->len = i;
+    }
   }
 
   if (sbuts->texuser) {
     ButsContextTexture *ct = sbuts->texuser;
-    BKE_id_remapper_apply(mappings, (ID **)&ct->texture, ID_REMAP_APPLY_DEFAULT);
+    if ((ID *)ct->texture == old_id) {
+      ct->texture = (Tex *)new_id;
+    }
     BLI_freelistN(&ct->users);
     ct->user = NULL;
   }