Bug 481994 - canUndo/canRedo called twice

* Check only once on the feature if canUndo/canRedo is possible
* Check canUndo in any case, as it is implemented on level of IFeature
* Use old interface method first, then new interface for canRedo
* Default for canRedo is true now, in case an entry has been undone it
can also be redone

Change-Id: I755fae7dddce649a872bb7e1a888001d7dc44475
1 file changed
tree: 550ee794a083b4caf342f85887a4234ba3e56635
  2. examples/
  3. features/
  4. parent/
  5. plugins/
  6. releng/
  7. tests/