[NI] Fix KotlinResolutionCandidate.isSuccessfull

Check if ConstrainSystem has any contradiction in 'isSuccessful'.
Otherwise we may erroneously think that there are some successful
candidates in 'TowerResolver.SuccessfullResultCollector.pushCandidates()'
and clear other unsuccessful ones (while they actually may have higher
applicability).

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/model/ResolutionCandidate.kt

@@ -145,7 +145,7 @@ class KotlinResolutionCandidate(
     override val isSuccessful: Boolean
         get() {
             processParts(stopOnFirstError = true)
-            return currentApplicability.isSuccess && variableApplicability.isSuccess
+            return currentApplicability.isSuccess && variableApplicability.isSuccess && !getSystem().hasContradiction
         }
 
     override val resultingApplicability: ResolutionCandidateApplicability