fix #420 CssLoader test case for slow networks
fix #420 CssLoader test case for slow networks

Fix a test case that fails when the browser is too slow to apply the css
rules of a newly loaded css file

fbasso/ariatemplates,fcapa/aria,ymeine/ariatemplates,benouat/ariatemplates,mlaval/ariatemplates,divdavem/ariatemplates,simonarbuckle/ariatemplates,divdavem/ariatemplates,fbasso/ariatemplates,mlaval/ariatemplates,vcarle/ariatemplates,ymeine/ariatemplates,benouat/ariatemplates,lsimone/ariatemplates,fcapa/aria,ariatemplates/ariatemplates,vcarle/ariatemplates,ariatemplates/ariatemplates,benouat/ariatemplates,fcapa/aria,fbasso/ariatemplates,lsimone/ariatemplates,simonarbuckle/ariatemplates,flongo/ariatemplates,ariatemplates/ariatemplates,simonarbuckle/ariatemplates,vcarle/ariatemplates,divdavem/ariatemplates,ymeine/ariatemplates,mlaval/ariatemplates