CORE-16981
The problem:
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- When opening "Open With..." dialog for a given file format, multiple MRU items are appended to registry : 2 items written, even if dialog is closed "cancel".
- Expected behavior : 1 MRU item if execute is selected and 0 MRU if cancel is selected.
Fix:
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- MRU item to be added when "Execute" is selected only.
- Once added, set the presence flag to avoid multiple MRU items being added later.