FIR/UAST: commonize UAnnotationMethod

plugins/uast-kotlin-base/src/org/jetbrains/uast/kotlin/declarations/BaseKotlinUAnnotationMethod.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2021 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.
+ */
+
+package org.jetbrains.uast.kotlin
+
+import org.jetbrains.kotlin.asJava.elements.KtLightMethod
+import org.jetbrains.kotlin.psi.KtParameter
+import org.jetbrains.uast.*
+
+abstract class BaseKotlinUAnnotationMethod(
+    psi: KtLightMethod,
+    givenParent: UElement?
+) : BaseKotlinUMethod(psi, psi.kotlinOrigin, givenParent), UAnnotationMethod {
+    override val psi: KtLightMethod = unwrap<UMethod, KtLightMethod>(psi)
+
+    override val uastDefaultValue: UExpression? by lz {
+        val annotationParameter = sourcePsi as? KtParameter ?: return@lz null
+        val defaultValue = annotationParameter.defaultValue ?: return@lz null
+        languagePlugin?.convertElement(defaultValue, this) as? UExpression
+    }
+}