[Native] Drop IrSerializationUtil file

Most methods from there are unused

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/objcexport/ObjCExportCodeGenerator.kt

@@ -22,7 +22,6 @@ import org.jetbrains.kotlin.backend.konan.llvm.objc.ObjCCodeGenerator
 import org.jetbrains.kotlin.backend.konan.llvm.objc.ObjCDataGenerator
 import org.jetbrains.kotlin.backend.konan.lower.getObjectClassInstanceFunction
 import org.jetbrains.kotlin.backend.konan.objcexport.*
-import org.jetbrains.kotlin.backend.konan.serialization.resolveFakeOverrideMaybeAbstract
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.incremental.components.NoLookupLocation
@@ -1535,7 +1534,7 @@ private fun ObjCExportCodeGenerator.itablePlace(irFunction: IrSimpleFunction): C
     assert(irFunction.isOverridable)
     val irClass = irFunction.parentAsClass
     return if (irClass.isInterface
-            && (irFunction.isReal || irFunction.resolveFakeOverrideMaybeAbstract().parent != context.irBuiltIns.anyClass.owner)
+            && (irFunction.isReal || irFunction.resolveFakeOverride(allowAbstract = true)?.parent != context.irBuiltIns.anyClass.owner)
     ) {
         context.getLayoutBuilder(irClass).itablePlace(irFunction)
     } else {

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

@@ -18,7 +18,6 @@ import org.jetbrains.kotlin.backend.konan.descriptors.synthesizedName
 import org.jetbrains.kotlin.backend.konan.ir.*
 import org.jetbrains.kotlin.backend.konan.llvm.IntrinsicType
 import org.jetbrains.kotlin.backend.konan.llvm.tryGetIntrinsicType
-import org.jetbrains.kotlin.backend.konan.serialization.resolveFakeOverrideMaybeAbstract
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
@@ -1062,7 +1061,7 @@ private class InteropTransformer(
         builder.at(expression)
         val function = expression.symbol.owner
 
-        if ((function as? IrSimpleFunction)?.resolveFakeOverrideMaybeAbstract()?.symbol
+        if ((function as? IrSimpleFunction)?.resolveFakeOverride(allowAbstract = true)?.symbol
                 == symbols.interopNativePointedRawPtrGetter) {
 
             // Replace by the intrinsic call to be handled by code generator:

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

@@ -1,55 +0,0 @@
-/*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.kotlin.backend.konan.serialization
-
-import org.jetbrains.kotlin.backend.konan.descriptors.resolveFakeOverride
-import org.jetbrains.kotlin.descriptors.*
-import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.util.resolveFakeOverride
-import org.jetbrains.kotlin.resolve.OverridingUtil
-
-// TODO: move me somewhere
-
-/**
- * Implementation of given method.
- *
- * TODO: this method is actually a part of resolve and probably duplicates another one
- */
-internal fun IrSimpleFunction.resolveFakeOverrideMaybeAbstract() = this.resolveFakeOverride(allowAbstract = true)!!
-
-internal fun IrProperty.resolveFakeOverrideMaybeAbstract() =
-        this.getter!!.resolveFakeOverrideMaybeAbstract().correspondingPropertySymbol!!.owner
-
-internal fun IrField.resolveFakeOverrideMaybeAbstract() =
-        this.correspondingPropertySymbol!!.owner.resolveFakeOverrideMaybeAbstract().backingField
-
-/**
- * Implementation of given method.
- *
- * TODO: this method is actually a part of resolve and probably duplicates another one
- */
-internal fun <T : CallableMemberDescriptor> T.resolveFakeOverrideMaybeAbstract(): Set<T> {
-    if (this.kind.isReal) {
-        return setOf(this)
-    } else {
-        val overridden = OverridingUtil.getOverriddenDeclarations(this)
-        val filtered = OverridingUtil.filterOutOverridden(overridden)
-        // TODO: is it correct to take first?
-        @Suppress("UNCHECKED_CAST")
-        return filtered as Set<T>
-    }
-}