Make DeckTask a bit more defensive.

Add an easy way to check things are called from the right task and add
that to DeckTask.

Add an easy way to log methods being called.
Correctly handle calls to constructors.

Make sure we always call the super constructor because they might set a
default style and this would be lost if we call it with zero.
Merge pull request #35 from flerda/v2.1-preference-constructors

Correctly handle calls to constructors.
Merge pull request #30 from flerda/defensive

Make DeckTask a bit more defensive.
Reformat CardBrowser.java.

This is to actually help merge another file that has been reformatted,
but it is always good to improve our code.
Merge pull request #38 from flerda/v2.1-card-browser

Reformat CardBrowser.java.