2. No-op backup/restore in BaseFilter.getDefaultFilterWrappers()

[elharo]

Affected version

HEAD

Bug description

File: src/main/java/org/apache/maven/shared/filtering/BaseFilter.java, lines 78–81

// backup values
boolean supportMultiLineFiltering = request.isSupportMultiLineFiltering();
request.setSupportMultiLineFiltering(supportMultiLineFiltering);

This reads the supportMultiLineFiltering flag from the request and immediately writes the same value back. The variable supportMultiLineFiltering is never used again. The comment says "backup values" but there is no corresponding restore. This appears to be leftover dead code from an incomplete refactoring.