[Plugin API] Add extension point to contribute synthetic properties

- needs to fix KT_41006

compiler/frontend/src/org/jetbrains/kotlin/resolve/extensions/SyntheticResolveExtension.kt

@@ -54,6 +54,9 @@ interface SyntheticResolveExtension {
                 override fun getSyntheticFunctionNames(thisDescriptor: ClassDescriptor): List<Name> =
                     instances.flatMap { withLinkageErrorLogger(it) { getSyntheticFunctionNames(thisDescriptor) } }
 
+                override fun getSyntheticPropertiesNames(thisDescriptor: ClassDescriptor): List<Name> =
+                    instances.flatMap { withLinkageErrorLogger(it) { getSyntheticPropertiesNames(thisDescriptor) } }
+
                 override fun generateSyntheticClasses(
                     thisDescriptor: ClassDescriptor, name: Name,
                     ctx: LazyClassContext, declarationProvider: ClassMemberDeclarationProvider,
@@ -142,6 +145,9 @@ interface SyntheticResolveExtension {
 
     fun getSyntheticFunctionNames(thisDescriptor: ClassDescriptor): List<Name> = emptyList()
 
+    @JvmDefault
+    fun getSyntheticPropertiesNames(thisDescriptor: ClassDescriptor): List<Name> = emptyList()
+
     fun getSyntheticNestedClassNames(thisDescriptor: ClassDescriptor): List<Name> = emptyList()
 
     /**

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyClassMemberScope.kt

@@ -90,6 +90,7 @@ open class LazyClassMemberScope(
 
         addDataClassMethods(result, location)
         addSyntheticFunctions(result, location)
+        addSyntheticVariables(result, location)
         addSyntheticCompanionObject(result, location)
         addSyntheticNestedClasses(result, location)
 
@@ -106,6 +107,7 @@ open class LazyClassMemberScope(
             by storageManager.createLazyValue {
                 mutableSetOf<Name>().apply {
                     addAll(declarationProvider.getDeclarationNames())
+                    addAll(c.syntheticResolveExtension.getSyntheticPropertiesNames(thisDescriptor))
                     supertypes.flatMapTo(this) {
                         it.memberScope.getVariableNames()
                     }
@@ -344,6 +346,15 @@ open class LazyClassMemberScope(
         }.toList())
     }
 
+    private fun addSyntheticVariables(result: MutableCollection<DeclarationDescriptor>, location: LookupLocation) {
+        result.addAll(c.syntheticResolveExtension.getSyntheticPropertiesNames(thisDescriptor).flatMap {
+            getContributedVariables(
+                it,
+                location
+            )
+        }.toList())
+    }
+
     private fun addSyntheticNestedClasses(result: MutableCollection<DeclarationDescriptor>, location: LookupLocation) {
         result.addAll(c.syntheticResolveExtension.getSyntheticNestedClassNames(thisDescriptor).mapNotNull {
             getContributedClassifier(

libraries/tools/kotlin-maven-serialization/pom.xml

@@ -74,6 +74,9 @@
                 </executions>
                 <configuration>
                     <jvmTarget>1.8</jvmTarget>
+                    <args>
+                        <arg>-Xjvm-default=enable</arg>
+                    </args>
                 </configuration>
             </plugin>
             <plugin>