D27632: Implement UString operator= to make gcc happy

[Albert Astals Cid]

aacid added a subscriber: porten.

REPOSITORY
  R314 KJs

REVISION DETAIL
  https://phabricator.kde.org/D27632

To: aacid
Cc: porten, kde-frameworks-devel, LeGast00n, cblack, GB_2, michaelh, ngraham, 
bruns