fixed #259 second case. (Switching between placeholder and suffix in ORKUnitTextField)
fixed #259 second case. (Switching between placeholder and suffix in ORKUnitTextField)

jade0425/ResearchKit,andyvand/ResearchKit,DrGo/ResearchKit,pawisoon/ResearchKit,jade0425/ResearchKit,weijentu/ResearchKit,cnbin/ResearchKit,lijie121210/ResearchKit,DrGo/ResearchKit,pawisoon/ResearchKit,wlads/ResearchKit,jtdavid/ResearchKit,utterances/ResearchKit,utterances/ResearchKit,KaiCode2/ResearchKit,YuanZhu-apple/ResearchKit,zhuzhengwei/ResearchKit,jeremiahyan/ResearchKit,cornellradiology/ResearchKit,shyamalschandra/ResearchKit,md0u80c9/ResearchKit,zdw19840929/ResearchKit,shazino/ResearchKit,oliverschaefer/ResearchKit,wakermahmud/ResearchKit,danoli3/ResearchKit,QuintilesRK/ResearchKit,solehayubi/ResearchKit,msdgwzhy6/ResearchKit,zdw19840929/ResearchKit,shyamalschandra/ResearchKit,boland25/ResearchKit,jarrelscy/ResearchKit,HarrisLee/ResearchKit,seantma/ResearchKit,YuanZhu-apple/ResearchKit,cnbin/ResearchKit,umerkhan-apple/ResearchKit,weijentu/ResearchKit,qualwas72/ResearchKit,msdgwzhy6/ResearchKit,chb/ResearchKit,mluedke2/ResearchKit,zhuzhengwei/ResearchKit,jimmyti/ResearchKit,AlexanderMazaletskiy/ResearchKit,md0u80c9/ResearchKit,zhuzhengwei/ResearchKit,HarrisLee/ResearchKit,umerkhan-apple/ResearchKit,cornelltech/ResearchKit,jarrelscy/ResearchKit,wakermahmud/ResearchKit,seantma/ResearchKit,cornellradiology/ResearchKit,CaueAlvesSilva/ResearchKit,qualwas72/ResearchKit,umerkhan-apple/ResearchKit,CaueAlvesSilva/ResearchKit,QuintilesRK/ResearchKit,md0u80c9/ResearchKit,seantma/ResearchKit,oliverschaefer/ResearchKit,YuanZhu-apple/ResearchKit,KaiCode2/ResearchKit,jimmyti/ResearchKit,msdgwzhy6/ResearchKit,qualwas72/ResearchKit,wlads/ResearchKit,jade0425/ResearchKit,zdw19840929/ResearchKit,AlexanderMazaletskiy/ResearchKit,HarrisLee/ResearchKit,boland25/ResearchKit,wakermahmud/ResearchKit,yuanhoujun/ResearchKit,shyamalschandra/ResearchKit,danoli3/ResearchKit,allen7wang/ResearchKit,shazino/ResearchKit,CaueAlvesSilva/ResearchKit,chb/ResearchKit,jarrelscy/ResearchKit,DrGo/ResearchKit,lijie121210/ResearchKit,mluedke2/ResearchKit,cornelltech/ResearchKit,lijie121210/ResearchKit,zhuzhengwei/ResearchKit,jeremiahyan/ResearchKit,shazino/ResearchKit,msdgwzhy6/ResearchKit,zdw19840929/ResearchKit,boland25/ResearchKit,cornelltech/ResearchKit,wlads/ResearchKit,KaiCode2/ResearchKit,danoli3/ResearchKit,CaueAlvesSilva/ResearchKit,andyvand/ResearchKit,oliverschaefer/ResearchKit,jimmyti/ResearchKit,solehayubi/ResearchKit,cornellradiology/ResearchKit,jeremiahyan/ResearchKit,andyvand/ResearchKit,yuanhoujun/ResearchKit,solehayubi/ResearchKit,allen7wang/ResearchKit,yuanhoujun/ResearchKit,chb/ResearchKit,weijentu/ResearchKit,boland25/ResearchKit,mluedke2/ResearchKit,weijentu/ResearchKit,md0u80c9/ResearchKit,pawisoon/ResearchKit,oliverschaefer/ResearchKit,lijie121210/ResearchKit,AlexanderMazaletskiy/ResearchKit,QuintilesRK/ResearchKit,jtdavid/ResearchKit,utterances/ResearchKit,cnbin/ResearchKit,YuanZhu-apple/ResearchKit,allen7wang/ResearchKit,cornellradiology/ResearchKit,qualwas72/ResearchKit,chb/ResearchKit