Ambiguous characters are treated like 'N' in find pattern algorithm when search on the reverse-complement strand is performed

Scenario:

1. Open "data/samples/Genbank/murine.gb".
2. Open "Search in Sequence" options panel tab.
3. Set "Substitute" algorithm. Check "Search with ambiguous bases" checkbox.
4. Ensure that the search is performed on both strands (it is the default value).
5. Enter the following pattern: "YYYGYY".
   Current result: 1725 results are found. The first result is (9..14). It is incorrect.

It happens because during the search the pattern is modified to it's reverse-complement to search on the reverse-complement strand. This operation is performed incorrectly: ambiguous characters are converted into 'N' instead of corresponding ambiguous character.