Revert implementation of fpsWhen to 0.14 version
Revert implementation of fpsWhen to 0.14 version

cc @jvoigtlaender and @jwmerrill in case I messed something up!

suryagaddipati/core,isaacsanders/core,ThomasWeiser/core,Dandandan/core,alexiamcdonald/elm-core,bradurani/core,rick68/core,rick68/core,martinos/core,martinos/core,colinmccabe/core,ThomasWeiser/core,simonh1000/core,rgrempel/core,laszlopandy/core,simonh1000/core,vilterp/core,Dandandan/core,bradurani/core,Pisys/core,suryagaddipati/core,vilterp/core,isaacsanders/core,Pisys/core,eeue56/core,colinmccabe/core,rgrempel/core,laszlopandy/core,eeue56/core,alexiamcdonald/elm-core