[Generator] Reference generator class in generated code files

generators/builtins/primitives/builders.kt

@@ -6,13 +6,14 @@
 package org.jetbrains.kotlin.generators.builtins.numbers.primitives
 
 import java.io.File
+import kotlin.reflect.KClass
 
 private fun String.shift(): String {
     return this.split(END_LINE).joinToString(separator = END_LINE) { if (it.isEmpty()) it else "    $it" }
 }
 
-internal fun file(init: FileBuilder.() -> Unit): FileBuilder {
-    val file = FileBuilder()
+internal fun file(builtBy: KClass<*>, init: FileBuilder.() -> Unit): FileBuilder {
+    val file = FileBuilder(builtBy.qualifiedName!!)
     file.init()
     return file
 }
@@ -76,7 +77,7 @@ internal abstract class AnnotatedAndDocumented {
     }
 }
 
-internal class FileBuilder : PrimitiveBuilder {
+internal class FileBuilder(private val builtBy: String) : PrimitiveBuilder {
     private val suppresses: MutableList<String> = mutableListOf()
     private val imports: MutableList<String> = mutableListOf()
     private val fileComments: MutableList<String> = mutableListOf()
@@ -105,6 +106,7 @@ internal class FileBuilder : PrimitiveBuilder {
             appendLine(File("license/COPYRIGHT_HEADER.txt").readText())
             appendLine()
             appendLine("// Auto-generated file. DO NOT EDIT!")
+            appendLine("// Generated by $builtBy")
             appendLine()
 
             if (suppresses.isNotEmpty()) {