Code review comment for lp:~smspillaz/unity/unity.fix_84037_864784_868120_872625

Instead of
  uScreen->_fbo = UnityFBO::Ptr (new UnityFBO (geometry));
you can go
  uScreen->_fbo.reset(new UnityFBO(geometry));

Saves a little typing (and it is more efficient in behaviour),

  UnityFBO::UnityFBO (CompRect geometry)
should be
  UnityFBO::UnityFBO(CompRect const& geometry)

Avoids an extra copy.