IR: Introduce IrClassifierSymbol.defaultType

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypes.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
@@ -10,7 +10,9 @@ import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrTypeParameter
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrClassifierSymbol
+import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
 import org.jetbrains.kotlin.ir.types.impl.*
+import org.jetbrains.kotlin.ir.util.defaultType
 import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.typeUtil.makeNotNullable
 import org.jetbrains.kotlin.types.typeUtil.makeNullable
@@ -96,6 +98,13 @@ private fun makeKotlinType(
     return classifier.descriptor.defaultType.replace(newArguments = kotlinTypeArguments).makeNullableAsSpecified(hasQuestionMark)
 }
 
+val IrClassifierSymbol.defaultType: IrType
+    get() = when (this) {
+        is IrClassSymbol -> owner.defaultType
+        is IrTypeParameterSymbol -> owner.defaultType
+        else -> error("Unexpected classifier symbol type $this")
+    }
+
 val IrTypeParameter.defaultType: IrType
     get() = IrSimpleTypeImpl(
         symbol,