Fix a bug when enabling back stroke in RecodedArea and RecodedPoint.
The field was not set back, leading to a problem when trying to render
something.
We want LegendUIChooser to be onTop when it is opened.
removing an useless LOGGER.error call
Solves two NPEs. When dealing with unique values, getValueReference is
null in RecodedLegend instances. field() should be called instead.
Merge remote-tracking branch 'upstream/master' into various
Uses ContainerItem rather than String in WKNComboBox.
This way, internationalization should not break the UI.
Merge pull request #533 from agueganno/various

Two bugfixes:

    1. The legend chooser was not set on top in the simple style editor.

    2. When using value classifications for area or points, there was a bug with
    stroke management. If you created your classification, disabled and enabled
    the stroke and finally changed the stroke for one of the created values, an
    exception was raised. The classification field was not set back, leading to
    the problem. Should be fixed.