Use cache for custom ClassDescriptors

Otherwise new ones are being created for each request, and their member scope is recomputed

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/kotlin/DeserializationComponentsForJava.kt

@@ -39,7 +39,7 @@ class DeserializationComponentsForJava(
 
     init {
         val localClassResolver = LocalClassResolverImpl()
-        val settings = JvmBuiltInsSettings(moduleDescriptor, { moduleDescriptor })
+        val settings = JvmBuiltInsSettings(moduleDescriptor, storageManager, { moduleDescriptor })
         components = DeserializationComponents(
                 storageManager, moduleDescriptor, classDataFinder, annotationAndConstantLoader, packageFragmentProvider, localClassResolver,
                 errorReporter, lookupTracker, FlexibleJavaClassifierTypeFactory, ClassDescriptorFactory.EMPTY,

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/kotlin/JvmBuiltInsSettings.kt

@@ -39,6 +39,7 @@ import org.jetbrains.kotlin.serialization.deserialization.PLATFORM_DEPENDENT_ANN
 import org.jetbrains.kotlin.serialization.deserialization.PlatformDependentDeclarationFilter
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedClassDescriptor
 import org.jetbrains.kotlin.storage.LockBasedStorageManager
+import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.types.DelegatingType
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.utils.DFS
@@ -49,6 +50,7 @@ import java.util.*
 
 open class JvmBuiltInsSettings(
         private val moduleDescriptor: ModuleDescriptor,
+        storageManager: StorageManager,
         deferredOwnerModuleDescriptor: () -> ModuleDescriptor
 ) : AdditionalClassPartsProvider, PlatformDependentDeclarationFilter {
     private val j2kClassMap = JavaToKotlinClassMap.INSTANCE
@@ -57,6 +59,8 @@ open class JvmBuiltInsSettings(
 
     private val mockSerializableType = createMockJavaIoSerializableType()
 
+    private val javaAnalogueClassesWithCustomSupertypeCache = storageManager.createCacheWithNotNullValues<FqName, ClassDescriptor>()
+
     private fun createMockJavaIoSerializableType(): KotlinType {
         val mockJavaIoPackageFragment = object : PackageFragmentDescriptorImpl(moduleDescriptor, FqName("java.io")) {
             override fun getMemberScope() = MemberScope.Empty
@@ -116,10 +120,11 @@ open class JvmBuiltInsSettings(
 
         val isMutable = j2kClassMap.isMutable(classDescriptor)
 
-        val fakeJavaClassDescriptor =
-                javaAnalogueDescriptor.copy(
-                        javaResolverCache = JavaResolverCache.EMPTY,
-                        additionalSupertypeClassDescriptor = kotlinMutableClassIfContainer)
+        val fakeJavaClassDescriptor = javaAnalogueClassesWithCustomSupertypeCache.computeIfAbsent(javaAnalogueDescriptor.fqNameSafe) {
+            javaAnalogueDescriptor.copy(
+                    javaResolverCache = JavaResolverCache.EMPTY,
+                    additionalSupertypeClassDescriptor = kotlinMutableClassIfContainer)
+        }
 
         val scope = fakeJavaClassDescriptor.unsubstitutedMemberScope
 

core/descriptor.loader.java/src/org/jetbrains/kotlin/platform/JvmBuiltIns.kt

@@ -38,7 +38,7 @@ class JvmBuiltIns(storageManager: StorageManager) : KotlinBuiltIns(storageManage
     // Here we know order in which KotlinBuiltIns constructor calls these methods
     override fun getPlatformDependentDeclarationFilter(): PlatformDependentDeclarationFilter {
         settings = JvmBuiltInsSettings(
-                builtInsModule,
+                builtInsModule, storageManager,
                 { ownerModuleDescriptor.sure { "JvmBuiltins has not been initialized properly" } }
         )