[FE 1.0] Remove CONSTRAINT_SYSTEM_FOR_OVERLOAD_RESOLUTION analysis flag

The constraint system for the old type inference is going to be removed.
Also, `CONSTRAINT_SYSTEM_FOR_OVERLOAD_RESOLUTION` isn't used in the production

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/KotlinResolutionStatelessCallbacksImpl.kt

@@ -104,10 +104,5 @@ class KotlinResolutionStatelessCallbacksImpl(
 
     override fun createConstraintSystemForOverloadResolution(
         constraintInjector: ConstraintInjector, builtIns: KotlinBuiltIns
-    ): SimpleConstraintSystem {
-        return if (languageVersionSettings.getFlag(AnalysisFlags.constraintSystemForOverloadResolution).forNewInference())
-            SimpleConstraintSystemImpl(constraintInjector, builtIns, kotlinTypeRefiner, languageVersionSettings)
-        else
-            ConstraintSystemBuilderImpl.forSpecificity()
-    }
+    ): SimpleConstraintSystem = SimpleConstraintSystemImpl(constraintInjector, builtIns, kotlinTypeRefiner, languageVersionSettings)
 }

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/BasicExpressionTypingVisitor.java

@@ -78,7 +78,6 @@ import org.jetbrains.kotlin.types.expressions.unqualifiedSuper.UnqualifiedSuperK
 import org.jetbrains.kotlin.types.typeUtil.TypeUtilsKt;
 import org.jetbrains.kotlin.util.OperatorNameConventions;
 
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;