Refactoring: move KtExpression.unpackFunctionLiteral to utils file

compiler/psi/src/org/jetbrains/kotlin/psi/KtLambdaArgument.kt

@@ -23,14 +23,4 @@ class KtLambdaArgument(node: ASTNode) : KtValueArgument(node), LambdaArgument {
     override fun getLambdaExpression(): KtLambdaExpression? = getArgumentExpression()?.unpackFunctionLiteral()
 }
 
-fun KtExpression.unpackFunctionLiteral(allowParentheses: Boolean = false): KtLambdaExpression? {
-    return when (this) {
-        is KtLambdaExpression -> this
-        is KtLabeledExpression -> baseExpression?.unpackFunctionLiteral(allowParentheses)
-        is KtAnnotatedExpression -> baseExpression?.unpackFunctionLiteral(allowParentheses)
-        is KtParenthesizedExpression -> if (allowParentheses) expression?.unpackFunctionLiteral(allowParentheses) else null
-        else -> null
-    }
-}
-
 

compiler/psi/src/org/jetbrains/kotlin/psi/ktElementUtils.kt

@@ -30,3 +30,13 @@ internal fun KtElement.deleteSemicolon() {
     val lastSiblingToDelete = PsiTreeUtil.skipSiblingsForward(sibling, PsiWhiteSpace::class.java)?.prevSibling ?: sibling
     parent.deleteChildRange(nextSibling, lastSiblingToDelete)
 }
+
+fun KtExpression.unpackFunctionLiteral(allowParentheses: Boolean = false): KtLambdaExpression? {
+    return when (this) {
+        is KtLambdaExpression -> this
+        is KtLabeledExpression -> baseExpression?.unpackFunctionLiteral(allowParentheses)
+        is KtAnnotatedExpression -> baseExpression?.unpackFunctionLiteral(allowParentheses)
+        is KtParenthesizedExpression -> if (allowParentheses) expression?.unpackFunctionLiteral(allowParentheses) else null
+        else -> null
+    }
+}