Workaround for unsupported per-pixel translucency

setBackground() throws an UnsupportedOperationException if per-pixel
translucency isn't supported and alpha is less than 1.0.

This should fix issue #230.
Merge pull request #231 from foutrelis/master

Workaround for unsupported per-pixel translucency
changelog update, thanks @foutrelis
Fixes issue #229, new playlists can be created by dropping songs from existing playlists on New Playlist list item. Kudos to @muckachina for incredible attention to detail when finding this bug.
Merge pull request #232 from frostwire/issue-229

Fixes issue #229, new playlists can be created by dropping songs from ex...
changelog
avoid NPE
Merge branch 'master' into swig