[CSOptimizer] Adopt to removal of TypeBase::isArrayType() by switching to isArray()

Author: xedin

lib/Sema/CSOptimizer.cpp

@@ -1195,7 +1195,7 @@ static void determineBestChoicesInContext(
         // since everything else is going to increase to score.
         if (options.contains(MatchFlag::Literal)) {
           if (isUnboundArrayType(candidateType))
-            return paramType->isArrayType() ? 0.3 : 0;
+            return paramType->isArray() ? 0.3 : 0;
 
           if (isUnboundDictionaryType(candidateType))
             return cs.isDictionaryType(paramType) ? 0.3 : 0;