[CSSolver] Shrinking should avoid solutions with implicit conversions
[CSSolver] Shrinking should avoid solutions with implicit conversions

Just like generic overloads, `shrink` should always avoid any solutions
with implicit conversions.

Reducing disjunction domains becaused on solutions with implicit
conversions could have negative performance impact due to the
increase in total number of solutions that have to be examined
as a result.

xwu/swift,apple/swift,benlangmuir/swift,parkera/swift,JGiola/swift,benlangmuir/swift,JGiola/swift,parkera/swift,JGiola/swift,parkera/swift,rudkx/swift,glessard/swift,rudkx/swift,rudkx/swift,rudkx/swift,hooman/swift,tkremenek/swift,gregomni/swift,apple/swift,xwu/swift,parkera/swift,rudkx/swift,atrick/swift,ahoppen/swift,hooman/swift,apple/swift,glessard/swift,ahoppen/swift,tkremenek/swift,tkremenek/swift,glessard/swift,roambotics/swift,apple/swift,glessard/swift,parkera/swift,xwu/swift,parkera/swift,benlangmuir/swift,atrick/swift,atrick/swift,apple/swift,apple/swift,hooman/swift,ahoppen/swift,JGiola/swift,tkremenek/swift,tkremenek/swift,hooman/swift,glessard/swift,benlangmuir/swift,benlangmuir/swift,xwu/swift,gregomni/swift,roambotics/swift,gregomni/swift,xwu/swift,JGiola/swift,ahoppen/swift,tkremenek/swift,hooman/swift,xwu/swift,roambotics/swift,atrick/swift,gregomni/swift,hooman/swift,benlangmuir/swift,atrick/swift,xwu/swift,gregomni/swift,hooman/swift,tkremenek/swift,roambotics/swift,gregomni/swift,roambotics/swift,atrick/swift,parkera/swift,ahoppen/swift,parkera/swift,glessard/swift,rudkx/swift,ahoppen/swift,JGiola/swift,roambotics/swift