[FIR] Introduce & use FirTypeRef.coneType

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/JavaUtils.kt

@@ -221,7 +221,7 @@ private fun FirTypeParameter.getErasedUpperBound(
 ): ConeKotlinType {
     if (this === potentiallyRecursiveTypeParameter) return defaultValue()
 
-    val firstUpperBound = this.bounds.first().coneTypeUnsafe<ConeKotlinType>()
+    val firstUpperBound = this.bounds.first().coneType
 
     return getErasedVersionOfFirstUpperBound(firstUpperBound, mutableSetOf(this, potentiallyRecursiveTypeParameter), defaultValue)
 }
@@ -256,7 +256,7 @@ private fun getErasedVersionOfFirstUpperBound(
             val current = firstUpperBound.lookupTag.typeParameterSymbol.fir
 
             if (alreadyVisitedParameters.add(current)) {
-                val nextUpperBound = current.bounds.first().coneTypeUnsafe<ConeKotlinType>()
+                val nextUpperBound = current.bounds.first().coneType
                 getErasedVersionOfFirstUpperBound(nextUpperBound, alreadyVisitedParameters, defaultValue)
             } else {
                 defaultValue()

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/enhancement/javaTypeUtils.kt

@@ -119,7 +119,7 @@ private fun coneFlexibleOrSimpleType(
             // TODO: we need enhancement for type parameter bounds for this code to work properly
             // At this moment, this condition is always true
             if (lookupTag.typeParameterSymbol.fir.bounds.any {
-                    val type = (it as FirResolvedTypeRef).type
+                    val type = it.coneType
                     type is ConeTypeParameterType || type.isNullable
                 }
             ) {