Initial version of codegen for inline classes

core/descriptors/src/org/jetbrains/kotlin/resolve/inlineClassesUtils.kt

@@ -6,9 +6,12 @@
 package org.jetbrains.kotlin.resolve
 
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 
 fun ClassDescriptor.underlyingRepresentation(): ValueParameterDescriptor? {
     if (!isInline) return null
     return unsubstitutedPrimaryConstructor?.valueParameters?.singleOrNull()
 }
+
+fun DeclarationDescriptor.isInlineClass() = this is ClassDescriptor && this.isInline