Refactor existiong *OptionsImpl classes.

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJsDceOptionsImpl.kt

@@ -17,14 +17,12 @@
 package org.jetbrains.kotlin.gradle.dsl
 
 import org.jetbrains.kotlin.cli.common.arguments.K2JSDceArguments
-import org.jetbrains.kotlin.cli.js.dce.K2JSDce
 
 internal class KotlinJsDceOptionsImpl : KotlinJsDceOptionsBase() {
     override var freeCompilerArgs: List<String> = listOf()
 
     override fun updateArguments(args: K2JSDceArguments) {
         super.updateArguments(args)
-        val freeArgsArray = (freeCompilerArgs as List<Any>).map(Any::toString).toTypedArray()
-        K2JSDce().parseArguments(freeArgsArray, args)
+        copyFreeCompilerArgsToArgs(args)
     }
 }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJsOptionsImpl.kt

@@ -23,8 +23,6 @@ internal class KotlinJsOptionsImpl : KotlinJsOptionsBase() {
 
     override fun updateArguments(args: K2JSCompilerArguments) {
         super.updateArguments(args)
-        // cast to List<Any> is important because in Groovy a GString can be inside of a list
-        val freeArgs = (freeCompilerArgs as List<Any>).map(Any::toString)
-        args.freeArgs.addAll(freeArgs)
+        copyFreeCompilerArgsToArgs(args)
     }
 }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinJvmOptionsImpl.kt

@@ -23,8 +23,6 @@ internal class KotlinJvmOptionsImpl : KotlinJvmOptionsBase() {
 
     override fun updateArguments(args: K2JVMCompilerArguments) {
         super.updateArguments(args)
-        // cast to List<Any> is important because in Groovy a GString can be inside of a list
-        val freeArgs = (freeCompilerArgs as List<Any>).map(Any::toString)
-        args.freeArgs.addAll(freeArgs)
+        copyFreeCompilerArgsToArgs(args)
     }
 }