Move PsiSourceElement to psi

compiler/frontend/src/org/jetbrains/kotlin/resolve/source/KotlinSourceElement.kt

@@ -16,7 +16,6 @@
 
 package org.jetbrains.kotlin.resolve.source
 
-import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.SourceElement
 import org.jetbrains.kotlin.psi.KtElement
 import org.jetbrains.kotlin.psi.KtPureElement
@@ -24,5 +23,3 @@ import org.jetbrains.kotlin.psi.KtPureElement
 class KotlinSourceElement(override val psi: KtElement) : PsiSourceElement
 
 fun KtPureElement?.toSourceElement(): SourceElement = if (this == null) SourceElement.NO_SOURCE else KotlinSourceElement(psiOrParent)
-
-fun SourceElement.getPsi(): PsiElement? = (this as? PsiSourceElement)?.psi

compiler/psi/src/org/jetbrains/kotlin/resolve/source/PsiSourceElement.kt

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
- *
- * 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.
+ * 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.kotlin.resolve.source
@@ -36,3 +25,5 @@ class PsiSourceFile(val psiFile: PsiFile) : SourceFile {
 
     override fun getName(): String? = psiFile.virtualFile?.name
 }
+
+fun SourceElement.getPsi(): PsiElement? = (this as? PsiSourceElement)?.psi