[ORKHeightPicker] Rename variables in internal method
[ORKHeightPicker] Rename variables in internal method

chb/ResearchKit,md0u80c9/ResearchKit,chb/ResearchKit,YuanZhu-apple/ResearchKit,cornelltech/ResearchKit,boland25/ResearchKit,boland25/ResearchKit,weijentu/ResearchKit,YuanZhu-apple/ResearchKit,md0u80c9/ResearchKit,jeremiahyan/ResearchKit,mluedke2/ResearchKit,chb/ResearchKit,YuanZhu-apple/ResearchKit,oliverschaefer/ResearchKit,YuanZhu-apple/ResearchKit,weijentu/ResearchKit,boland25/ResearchKit,weijentu/ResearchKit,boland25/ResearchKit,md0u80c9/ResearchKit,oliverschaefer/ResearchKit,chb/ResearchKit,oliverschaefer/ResearchKit,md0u80c9/ResearchKit,mluedke2/ResearchKit,jeremiahyan/ResearchKit,cornelltech/ResearchKit,oliverschaefer/ResearchKit,jeremiahyan/ResearchKit,weijentu/ResearchKit,mluedke2/ResearchKit,cornelltech/ResearchKit