[FIR] Move sealedInheritors declaration data to :fir:tree module

compiler/fir/fir-deserialization/src/org/jetbrains/kotlin/fir/deserialization/ClassDeserialization.kt

@@ -17,7 +17,6 @@ import org.jetbrains.kotlin.fir.declarations.impl.FirResolvedDeclarationStatusIm
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.resolve.providers.impl.FirCloneableSymbolProvider.Companion.CLONE
 import org.jetbrains.kotlin.fir.resolve.providers.impl.FirCloneableSymbolProvider.Companion.CLONEABLE_CLASS_ID
-import org.jetbrains.kotlin.fir.resolve.transformers.sealedInheritors
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
 import org.jetbrains.kotlin.fir.symbols.CallableId
 import org.jetbrains.kotlin.fir.symbols.ConeTypeParameterLookupTag

compiler/fir/fir-serialization/src/org/jetbrains/kotlin/fir/serialization/FirElementSerializer.kt

@@ -29,7 +29,6 @@ import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.inference.isSuspendFunctionType
 import org.jetbrains.kotlin.fir.resolve.inference.suspendFunctionTypeToFunctionTypeWithContinuation
 import org.jetbrains.kotlin.fir.resolve.toSymbol
-import org.jetbrains.kotlin.fir.resolve.transformers.sealedInheritors
 import org.jetbrains.kotlin.fir.serialization.constant.EnumValue
 import org.jetbrains.kotlin.fir.serialization.constant.IntValue
 import org.jetbrains.kotlin.fir.serialization.constant.StringValue

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirSealedClassInheritorsProcessor.kt

@@ -95,7 +95,3 @@ class FirSealedClassInheritorsProcessor(
     }
 
 }
-
-object SealedClassInheritorsKey : FirDeclarationDataKey()
-
-var FirRegularClass.sealedInheritors: List<ClassId>? by FirDeclarationDataRegistry.data(SealedClassInheritorsKey)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/SealedClassInheritors.kt

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.declarations
+
+import org.jetbrains.kotlin.name.ClassId
+
+object SealedClassInheritorsKey : FirDeclarationDataKey()
+
+var FirRegularClass.sealedInheritors: List<ClassId>? by FirDeclarationDataRegistry.data(SealedClassInheritorsKey)