[Gradle, JS] Use experimental dce annotation

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/dsl/ExperimentalDce.kt

@@ -0,0 +1,10 @@
+/*
+ * Copyright 2010-2019 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.targets.js.dsl
+
+@Experimental
+@Target(AnnotationTarget.FUNCTION)
+annotation class ExperimentalDce

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/dsl/KotlinJsTargetDsl.kt

@@ -61,7 +61,10 @@ interface KotlinJsBrowserDsl : KotlinJsSubTargetDsl {
         }
     }
 
+    @ExperimentalDce
     fun dceTask(body: KotlinJsDce.() -> Unit)
+
+    @ExperimentalDce
     fun dceTask(fn: Closure<*>) {
         dceTask {
             ConfigureUtil.configure(fn, this)

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/subtargets/KotlinBrowserJs.kt

@@ -14,6 +14,7 @@ import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJsCompilation
 import org.jetbrains.kotlin.gradle.targets.js.KotlinJsTarget
 import org.jetbrains.kotlin.gradle.targets.js.dsl.BuildVariant
 import org.jetbrains.kotlin.gradle.targets.js.dsl.BuildVariantKind
+import org.jetbrains.kotlin.gradle.targets.js.dsl.ExperimentalDce
 import org.jetbrains.kotlin.gradle.targets.js.dsl.KotlinJsBrowserDsl
 import org.jetbrains.kotlin.gradle.targets.js.nodejs.NodeJsRootPlugin
 import org.jetbrains.kotlin.gradle.targets.js.npm.npmProject
@@ -56,6 +57,7 @@ open class KotlinBrowserJs @Inject constructor(target: KotlinJsTarget) :
         (project.tasks.getByName(webpackTaskName) as KotlinWebpack).body()
     }
 
+    @ExperimentalDce
     override fun dceTask(body: KotlinJsDce.() -> Unit) {
         dceConfigurations.add(body)
     }