[Gradle, JS] Js compiler type in interface

libraries/tools/kotlin-gradle-plugin-api/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinJsCompilerTypeHolder.kt

@@ -0,0 +1,10 @@
+/*
+ * Copyright 2010-2020 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.gradle.plugin
+
+interface KotlinJsCompilerTypeHolder {
+    val defaultJsCompilerType: JsCompilerType
+}