Remove unused typedef.
Remove unused typedef.

NSExceptional/FLEX,NSExceptional/FLEX,Xiaobin0860/FLEX,hoaquo/FLEX,BrianBatchelder/FLEX,fbernardo/FLEX,tttpeng/FLEX-DatabaseBrowser,programming086/FLEX,Flipboard/FLEX,Kingside/FLEX,jdk89757/FLEX,evliu/FLEX,Automatic/FLEX,tttpeng/FLEX,otatime/FLEX,DaidoujiChen/FLEX,Flipboard/FLEX,pjebs/FLEX,hugo-/FLEX,lintaoSuper/FLEX