Gradle. Make nativeExtensions in KotlinCompilation optional

idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/KotlinMPPGradleProjectResolver.kt

@@ -492,7 +492,7 @@ open class KotlinMPPGradleProjectResolver : AbstractProjectResolverExtensionComp
             val substitutedDependencies: List<ExternalDependency>
         ) {
             val konanTarget: String?
-                get() = compilation.nativeExtensions.konanTarget
+                get() = compilation.nativeExtensions?.konanTarget
 
             val dependencyNames: Map<String, ExternalDependency> by lazy {
                 substitutedDependencies.associateBy { it.name.removeSuffixIfPresent(" [$konanTarget]") }

idea/kotlin-gradle-tooling/src/KotlinMPPGradleModel.kt

@@ -94,7 +94,7 @@ interface KotlinCompilationArguments : Serializable {
 }
 
 interface KotlinNativeCompilationExtensions : Serializable {
-    val konanTarget: String? // represents org.jetbrains.kotlin.konan.target.KonanTarget
+    val konanTarget: String // represents org.jetbrains.kotlin.konan.target.KonanTarget
 }
 
 interface KotlinCompilation : KotlinModule {
@@ -105,7 +105,7 @@ interface KotlinCompilation : KotlinModule {
     val disambiguationClassifier: String?
     val platform: KotlinPlatform
     val kotlinTaskProperties: KotlinTaskProperties
-    val nativeExtensions: KotlinNativeCompilationExtensions
+    val nativeExtensions: KotlinNativeCompilationExtensions?
 
     companion object {
         const val MAIN_COMPILATION_NAME = "main"

idea/kotlin-gradle-tooling/src/KotlinMPPGradleModelBuilder.kt

@@ -526,7 +526,7 @@ class KotlinMPPGradleModelBuilder : ModelBuilderService {
                 it.invoke(konanTarget) as? String
             }
         }
-        val nativeExtensions = KotlinNativeCompilationExtensionsImpl(konanTarget)
+        val nativeExtensions = konanTarget?.let(::KotlinNativeCompilationExtensionsImpl)
 
         return KotlinCompilationImpl(
             gradleCompilation.name,

idea/kotlin-gradle-tooling/src/KotlinMPPGradleModelImpl.kt

@@ -104,7 +104,7 @@ data class KotlinCompilationArgumentsImpl(
 }
 
 data class KotlinNativeCompilationExtensionsImpl(
-    override val konanTarget: String? = null
+    override val konanTarget: String
 ) : KotlinNativeCompilationExtensions {
     constructor(extensions: KotlinNativeCompilationExtensions) : this(extensions.konanTarget)
 }
@@ -117,7 +117,7 @@ data class KotlinCompilationImpl(
     override val arguments: KotlinCompilationArguments,
     override val dependencyClasspath: Array<String>,
     override val kotlinTaskProperties: KotlinTaskProperties,
-    override val nativeExtensions: KotlinNativeCompilationExtensions
+    override val nativeExtensions: KotlinNativeCompilationExtensions?
 ) : KotlinCompilation {
 
     // create deep copy
@@ -133,7 +133,7 @@ data class KotlinCompilationImpl(
         KotlinCompilationArgumentsImpl(kotlinCompilation.arguments),
         kotlinCompilation.dependencyClasspath,
         KotlinTaskPropertiesImpl(kotlinCompilation.kotlinTaskProperties),
-        KotlinNativeCompilationExtensionsImpl(kotlinCompilation.nativeExtensions)
+        kotlinCompilation.nativeExtensions?.let(::KotlinNativeCompilationExtensionsImpl)
     ) {
         disambiguationClassifier = kotlinCompilation.disambiguationClassifier
         platform = kotlinCompilation.platform