Bug 1844: When dragging file via temporary directory it is deleted too early

https://winscp.net/tracker/1844

Source commit: 544d85c8d7e4bb1163d36cce8ed34313578733ce

source/forms/CustomScpExplorer.cpp

@@ -7526,7 +7526,7 @@ bool __fastcall TCustomScpExplorerForm::DDGetTarget(
 void __fastcall TCustomScpExplorerForm::AddDelayedDirectoryDeletion(
   const UnicodeString TempDir, int SecDelay)
 {
-  TDateTime Alarm = Now() + (double)((double)SecDelay*OneMillisecond);
+  TDateTime Alarm = IncSecond(Now(), SecDelay);
   FDelayedDeletionList->AddObject(TempDir, reinterpret_cast<TObject*>(Alarm.FileDate()));
   if (FDelayedDeletionTimer == NULL)
   {