[Native] Drop KonanFileMetadataSource class

Replaced it with more common `DescriptorMetadataSource.File`

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

@@ -24,6 +24,7 @@ import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.ir.IrBuiltIns
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.builders.TranslationPluginContext
+import org.jetbrains.kotlin.ir.declarations.DescriptorMetadataSource
 import org.jetbrains.kotlin.ir.linkage.IrDeserializer
 import org.jetbrains.kotlin.ir.linkage.partial.partialLinkageConfig
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
@@ -248,9 +249,9 @@ internal fun PsiToIrContext.psiToIr(
                 (modules.values + mainModule).single { it.descriptor == this.stdlibModule }
     }
 
-    mainModule.files.forEach { it.metadata = KonanFileMetadataSource(mainModule) }
+    mainModule.files.forEach { it.metadata = DescriptorMetadataSource.File(listOf(mainModule.descriptor)) }
     modules.values.forEach { module ->
-        module.files.forEach { it.metadata = KonanFileMetadataSource(module) }
+        module.files.forEach { it.metadata = DescriptorMetadataSource.File(listOf(module.descriptor)) }
     }
 
     return if (isProducingLibrary) {

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

@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.backend.konan.descriptors.allOverriddenFunctions
 import org.jetbrains.kotlin.backend.konan.descriptors.isFromInteropLibrary
 import org.jetbrains.kotlin.backend.konan.descriptors.isInteropLibrary
 import org.jetbrains.kotlin.backend.konan.llvm.KonanMetadata
-import org.jetbrains.kotlin.backend.konan.serialization.KonanFileMetadataSource
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.ir.IrBuiltIns
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
@@ -99,13 +98,14 @@ private fun IrClass.getOverridingOf(function: IrFunction) = (function as? IrSimp
 }
 
 val ModuleDescriptor.konanLibrary get() = (this.klibModuleOrigin as? DeserializedKlibModuleOrigin)?.library
-val IrModuleFragment.konanLibrary get() = descriptor.konanLibrary
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
-val IrPackageFragment.konanLibrary : KotlinLibrary?
+val IrPackageFragment.konanLibrary: KotlinLibrary?
     get() {
         if (this is IrFile) {
-            (metadata as? KonanFileMetadataSource)?.module?.konanLibrary?.let { return it }
+            val fileMetadata = metadata as? DescriptorMetadataSource.File
+            val moduleDescriptor = fileMetadata?.descriptors?.singleOrNull() as? ModuleDescriptor
+            moduleDescriptor?.konanLibrary?.let { return it }
         }
         return this.packageFragmentDescriptor.containingDeclaration.konanLibrary
     }

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

@@ -1162,8 +1162,3 @@ internal class KonanIrLinker(
                     }
         }
 }
-
-class KonanFileMetadataSource(val module: IrModuleFragment) : MetadataSource.File {
-    override val name: Name? = null
-    override var serializedIr: ByteArray? = null
-}