Support nullable callable references in FIR resolve

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedQualifier.kt

@@ -25,6 +25,7 @@ abstract class FirResolvedQualifier : FirPureAbstractElement(), FirExpression {
     abstract val packageFqName: FqName
     abstract val relativeClassFqName: FqName?
     abstract val classId: ClassId?
+    abstract val safe: Boolean
     abstract val typeArguments: List<FirTypeProjection>
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitResolvedQualifier(this, data)

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirResolvedQualifierImpl.kt

@@ -24,7 +24,8 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirResolvedQualifierImpl(
     override val source: FirSourceElement?,
     override var packageFqName: FqName,
-    override var relativeClassFqName: FqName?
+    override var relativeClassFqName: FqName?,
+    override var safe: Boolean
 ) : FirResolvedQualifier(), FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()