Native: fix bug in KType support affecting only stdlib

Don't use IrClass.declarations to find enum entries during lowerings,
because this enum might already be lowered and thus have all entries
removed.

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/ir/Ir.kt

@@ -9,6 +9,7 @@ import org.jetbrains.kotlin.backend.common.COROUTINE_SUSPENDED_NAME
 import org.jetbrains.kotlin.backend.common.ir.Ir
 import org.jetbrains.kotlin.backend.common.ir.Symbols
 import org.jetbrains.kotlin.backend.konan.*
+import org.jetbrains.kotlin.backend.konan.descriptors.enumEntries
 import org.jetbrains.kotlin.backend.konan.descriptors.kotlinNativeInternal
 import org.jetbrains.kotlin.backend.konan.llvm.findMainEntryPoint
 import org.jetbrains.kotlin.backend.konan.lower.TestProcessor
@@ -23,6 +24,7 @@ import org.jetbrains.kotlin.incremental.components.NoLookupLocation
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.ir.symbols.IrEnumEntrySymbol
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.types.IrType
@@ -455,6 +457,14 @@ internal class KonanSymbols(
 
     val kType = symbolTable.referenceClass(context.reflectionTypes.kType)
     val kVariance = symbolTable.referenceClass(context.reflectionTypes.kVariance)
+    val kVarianceIn = getKVarianceEnumEntry("IN")
+    val kVarianceOut = getKVarianceEnumEntry("OUT")
+    val kVarianceInvariant = getKVarianceEnumEntry("INVARIANT")
+
+    private fun getKVarianceEnumEntry(name: String): IrEnumEntrySymbol {
+        val descriptor = context.reflectionTypes.kVariance.enumEntries.single { it.name.asString() == name }
+        return symbolTable.referenceEnumEntry(descriptor)
+    }
 
     val getClassTypeInfo = internalFunction("getClassTypeInfo")
     val getObjectTypeInfo = internalFunction("getObjectTypeInfo")

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/ReflectionSupport.kt

@@ -126,20 +126,15 @@ internal class KTypeGenerator(
         else -> parent.fqNameForIrSerialization.asString()
     }
 
-    private val Variance.kVarianceName: String
-        get() = when (this) {
-            Variance.INVARIANT -> "INVARIANT"
-            Variance.IN_VARIANCE -> "IN"
-            Variance.OUT_VARIANCE -> "OUT"
-        }
-
     private fun IrBuilderWithScope.irKVariance(variance: Variance) =
             IrGetEnumValueImpl(
                     startOffset, endOffset,
                     symbols.kVariance.defaultType,
-                    symbols.kVariance.owner.declarations
-                            .filterIsInstance<IrEnumEntry>()
-                            .single { it.name.asString() == variance.kVarianceName }.symbol
+                    when (variance) {
+                        Variance.INVARIANT -> symbols.kVarianceInvariant
+                        Variance.IN_VARIANCE -> symbols.kVarianceIn
+                        Variance.OUT_VARIANCE -> symbols.kVarianceOut
+                    }
             )
 
     private fun <T> IrBuilderWithScope.irKTypeLikeList(