FIR: precise lookupTag parameter of ConeTypeVariableType as it always accepts ConeTypeVariableTypeConstructor

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/ConeTypeCompatibilityChecker.kt

@@ -239,9 +239,8 @@ object ConeTypeCompatibilityChecker {
             is ConeClassErrorType -> emptySet() // Ignore error types
             is ConeLookupTagBasedType -> when (this) {
                 is ConeClassLikeType -> setOf(this)
-                is ConeTypeVariableType -> when (val tag = lookupTag) {
-                    is ConeTypeVariableTypeConstructor -> (tag.originalTypeParameter as? ConeTypeParameterLookupTag)?.typeParameterSymbol.collectUpperBounds()
-                    else -> throw IllegalStateException("missing branch for ${lookupTag.javaClass.name}")
+                is ConeTypeVariableType -> {
+                    (lookupTag.originalTypeParameter as? ConeTypeParameterLookupTag)?.typeParameterSymbol.collectUpperBounds()
                 }
                 is ConeTypeParameterType -> lookupTag.typeParameterSymbol.collectUpperBounds()
                 else -> throw IllegalStateException("missing branch for ${javaClass.name}")

compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/ConeTypes.kt

@@ -226,7 +226,7 @@ data class ConeCapturedType(
 
 data class ConeTypeVariableType(
     override val nullability: ConeNullability,
-    override val lookupTag: ConeClassifierLookupTag,
+    override val lookupTag: ConeTypeVariableTypeConstructor,
     override val attributes: ConeAttributes = ConeAttributes.Empty,
 ) : ConeLookupTagBasedType() {
     override val typeArguments: Array<out ConeTypeProjection> get() = emptyArray()