FIR: support type alias resolve

compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirRenderer.kt

@@ -393,6 +393,9 @@ class FirRenderer(builder: StringBuilder) : FirVisitorVoid() {
                         is ConeKotlinType -> it.asString()
                     }
                 })
+                if (this is ConeAbbreviatedType) {
+                    sb.append(" = ${this.directExpansion.asString()}")
+                }
                 sb.toString()
             }
             else -> "Unsupported: $this"

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirTypeAliasImpl.kt

@@ -8,9 +8,12 @@ package org.jetbrains.kotlin.fir.declarations.impl
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibility
+import org.jetbrains.kotlin.fir.FirElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirTypeAlias
+import org.jetbrains.kotlin.fir.transformSingle
 import org.jetbrains.kotlin.fir.types.FirType
+import org.jetbrains.kotlin.fir.visitors.FirTransformer
 import org.jetbrains.kotlin.name.Name
 
 class FirTypeAliasImpl(
@@ -18,5 +21,11 @@ class FirTypeAliasImpl(
     psi: PsiElement?,
     name: Name,
     visibility: Visibility,
-    override val abbreviatedType: FirType
-) : FirAbstractMemberDeclaration(session, psi, name, visibility, Modality.FINAL), FirTypeAlias
+    override var abbreviatedType: FirType
+) : FirAbstractMemberDeclaration(session, psi, name, visibility, Modality.FINAL), FirTypeAlias {
+    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirElement {
+        abbreviatedType = abbreviatedType.transformSingle(transformer, data)
+
+        return this
+    }
+}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/FirResolvedType.kt

@@ -13,4 +13,6 @@ interface FirResolvedType : FirTypeWithNullability {
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R =
         visitor.visitResolvedType(this, data)
-}
+}
+
+inline fun <reified T> FirType.coneTypeUnsafe() = (this as FirResolvedType).type as T