Parcelable: Add CREATOR field (and other generated declarations) in light classes (KT-19300, KT-19853)

compiler/backend/src/org/jetbrains/kotlin/codegen/ImplementationBodyCodegen.java

@@ -392,10 +392,12 @@ public class ImplementationBodyCodegen extends ClassBodyCodegen {
         if (context.closure != null)
             genClosureFields(context.closure, v, typeMapper);
 
-        if (state.getClassBuilderMode() == ClassBuilderMode.LIGHT_CLASSES) return;
-
         for (ExpressionCodegenExtension extension : ExpressionCodegenExtension.Companion.getInstances(state.getProject())) {
-            extension.generateClassSyntheticParts(this);
+            if (state.getClassBuilderMode() != ClassBuilderMode.LIGHT_CLASSES
+                || extension.getShouldGenerateClassSyntheticPartsInLightClassesMode()
+            ) {
+                extension.generateClassSyntheticParts(this);
+            }
         }
     }
 

compiler/backend/src/org/jetbrains/kotlin/codegen/extensions/ExpressionCodegenExtension.kt

@@ -47,4 +47,7 @@ interface ExpressionCodegenExtension {
     fun applyFunction(receiver: StackValue, resolvedCall: ResolvedCall<*>, c: Context): StackValue? = null
 
     fun generateClassSyntheticParts(codegen: ImplementationBodyCodegen) {}
+
+    val shouldGenerateClassSyntheticPartsInLightClassesMode: Boolean
+        get() = false
 }