Load JDK 8 platform implementations class without reflection

Also remove search for other platform implementation classes because
now the first match should be found in the same jar

Helps to avoid GraalVM related reflection problems in KT-51579

libraries/stdlib/jvm/build.gradle

@@ -15,6 +15,11 @@ configurations {
 }
 
 sourceSets {
+    compileOnlyDeclarations {
+        java {
+            srcDir 'compileOnly'
+        }
+    }
     main {
         java {
             srcDir "${rootDir}/core/builtins/src"
@@ -74,6 +79,7 @@ dependencies {
 
     api group: 'org.jetbrains', name: 'annotations', version:'13.0'
 
+    compileOnly sourceSets.compileOnlyDeclarations.output
     mainJdk7Api sourceSets.main.output
     mainJdk8Api sourceSets.main.output
     mainJdk8Api sourceSets.mainJdk7.output
@@ -176,6 +182,14 @@ compileMainJdk8Kotlin {
     kotlinOptions.moduleName = "kotlin-stdlib-jdk8"
 }
 
+compileCompileOnlyDeclarationsKotlin {
+    kotlinOptions {
+        freeCompilerArgs = [
+                "-Xallow-kotlin-package",
+        ]
+    }
+}
+
 compileTestKotlin {
     kotlinOptions {
         freeCompilerArgs += [

libraries/stdlib/jvm/compileOnly/JDK8PlatformImplementations.kt

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2010-2023 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 kotlin.internal.jdk8
+
+// forward-reference declaration of JDK8PlatformImplementations
+// declared in the source set compiled against JDK 8
+// used in the source set compiled against JDK 6
+public open class JDK8PlatformImplementations()

libraries/stdlib/jvm/src/kotlin/internal/PlatformImplementations.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2023 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.
  */
 
@@ -47,22 +47,8 @@ internal open class PlatformImplementations {
 
 
 @JvmField
-internal val IMPLEMENTATIONS: PlatformImplementations = run {
-    try {
-        return@run castToBaseType<PlatformImplementations>(Class.forName("kotlin.internal.jdk8.JDK8PlatformImplementations").newInstance())
-    } catch (e: ClassNotFoundException) { }
-    try {
-        return@run castToBaseType<PlatformImplementations>(Class.forName("kotlin.internal.JRE8PlatformImplementations").newInstance())
-    } catch (e: ClassNotFoundException) { }
-    try {
-        return@run castToBaseType<PlatformImplementations>(Class.forName("kotlin.internal.jdk7.JDK7PlatformImplementations").newInstance())
-    } catch (e: ClassNotFoundException) { }
-    try {
-        return@run castToBaseType<PlatformImplementations>(Class.forName("kotlin.internal.JRE7PlatformImplementations").newInstance())
-    } catch (e: ClassNotFoundException) { }
-
-    PlatformImplementations()
-}
+internal val IMPLEMENTATIONS: PlatformImplementations =
+    castToBaseType<PlatformImplementations>(kotlin.internal.jdk8.JDK8PlatformImplementations())
 
 @kotlin.internal.InlineOnly
 private inline fun <reified T : Any> castToBaseType(instance: Any): T {