SL-14270 Crash fix

indra/llui/llfolderviewmodel.cpp

@@ -50,7 +50,14 @@ LLFolderViewModelItemCommon::LLFolderViewModelItemCommon(LLFolderViewModelInterf
 
 LLFolderViewModelItemCommon::~LLFolderViewModelItemCommon()
 {
-    clearChildren();
+    // Children don't belong to model, but to LLFolderViewItem, just mark them as having no parent
+    std::for_each(mChildren.begin(), mChildren.end(), [](LLFolderViewModelItem* c) {c->setParent(NULL); });
+
+    // Don't leave dead pointer in parent
+    if (mParent)
+    {
+        mParent->removeChild(this);
+    }
 }
 
 void LLFolderViewModelItemCommon::dirtyFilter()