[light classes] move KtLightElementBase to light-classes-base module

^KT-53097

compiler/light-classes-base/src/org/jetbrains/kotlin/asJava/elements/KtLightElementBase.kt

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
+ * Copyright 2010-2022 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.
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
  */
 
 package org.jetbrains.kotlin.asJava.elements
@@ -29,7 +18,7 @@ abstract class KtLightElementBase(private var parent: PsiElement) : LightElement
 
     abstract val kotlinOrigin: KtElement?
 
-    internal fun setParent(newParent: PsiElement) {
+    fun setParent(newParent: PsiElement) {
         parent = newParent
     }
 
@@ -53,4 +42,4 @@ abstract class KtLightElementBase(private var parent: PsiElement) : LightElement
         return origin.isEquivalentTo(another) ||
                 (another is KtLightElementBase && origin.isEquivalentTo(another.kotlinOrigin))
     }
-}
+}