Re-run autoplacement after symbol replacement (when appropriate).

Also prevents an internal wxWidgets assert by clearing grid
selection before deleting rows.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/15541

(cherry picked from commit 377ffb00b0)

eeschema/dialogs/dialog_change_symbols.cpp

@@ -702,6 +702,10 @@ int DIALOG_CHANGE_SYMBOLS::processSymbols( const std::map<SCH_SYMBOL*,
 
         symbol->SetSchSymbolLibraryName( wxEmptyString );
         screen->Append( symbol );
+
+        if( resetPositions )
+            symbol->AutoAutoplaceFields( screen );
+
         frame->GetCanvas()->GetView()->Update( symbol );
 
         msg = getSymbolReferences( *symbol, symbol_change_info.m_LibId );

eeschema/dialogs/dialog_lib_symbol_properties.cpp

@@ -592,6 +592,7 @@ void DIALOG_LIB_SYMBOL_PROPERTIES::OnDeleteField( wxCommandEvent& event )
     }
 
     m_grid->CommitPendingChanges( true /* quiet mode */ );
+    m_grid->ClearSelection();
 
     // Reverse sort so deleting a row doesn't change the indexes of the other rows.
     selectedRows.Sort( []( int* first, int* second ) { return *second - *first; } );