[FIR] make FirPropertyAccessor#propertySymbol non-nullable

we need it to restore property accessor by property

^KT-54311

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirPropertyAccessor.kt

@@ -42,7 +42,7 @@ abstract class FirPropertyAccessor : FirFunction(), FirContractDescriptionOwner,
     abstract override val body: FirBlock?
     abstract override val contractDescription: FirContractDescription
     abstract override val symbol: FirPropertyAccessorSymbol
-    abstract val propertySymbol: FirPropertySymbol?
+    abstract val propertySymbol: FirPropertySymbol
     abstract val isGetter: Boolean
     abstract val isSetter: Boolean
     abstract override val annotations: List<FirAnnotation>

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyAccessorBuilder.kt

@@ -60,7 +60,7 @@ class FirPropertyAccessorBuilder : FirFunctionBuilder, FirAnnotationContainerBui
     override var body: FirBlock? = null
     var contractDescription: FirContractDescription = FirEmptyContractDescription
     lateinit var symbol: FirPropertyAccessorSymbol
-    var propertySymbol: FirPropertySymbol? = null
+    lateinit var propertySymbol: FirPropertySymbol
     var isGetter: Boolean by kotlin.properties.Delegates.notNull<Boolean>()
     override val annotations: MutableList<FirAnnotation> = mutableListOf()
     val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt

@@ -53,7 +53,7 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
     override var body: FirBlock?,
     override var contractDescription: FirContractDescription,
     override val symbol: FirPropertyAccessorSymbol,
-    override val propertySymbol: FirPropertySymbol?,
+    override val propertySymbol: FirPropertySymbol,
     override val isGetter: Boolean,
     override val annotations: MutableList<FirAnnotation>,
     override val typeParameters: MutableList<FirTypeParameter>,

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirDefaultPropertyAccessor.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2022 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.
  */
 
@@ -64,7 +64,7 @@ abstract class FirDefaultPropertyAccessor(
     typeParameters = mutableListOf(),
 ) {
     override val dispatchReceiverType: ConeSimpleKotlinType?
-        get() = propertySymbol?.dispatchReceiverType
+        get() = propertySymbol.dispatchReceiverType
 
     final override var body: FirBlock?
         get() = null

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/synthetic/FirSyntheticPropertyAccessor.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2022 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.
  */
 
@@ -24,7 +24,8 @@ import org.jetbrains.kotlin.serialization.deserialization.descriptors.Deserializ
 
 class FirSyntheticPropertyAccessor(
     val delegate: FirSimpleFunction,
-    override val isGetter: Boolean
+    override val isGetter: Boolean,
+    override val propertySymbol: FirPropertySymbol,
 ) : FirPropertyAccessor() {
     override val source: KtSourceElement?
         get() = delegate.source
@@ -78,9 +79,6 @@ class FirSyntheticPropertyAccessor(
     override val contextReceivers: List<FirContextReceiver>
         get() = emptyList()
 
-    // NB: unused
-    override val propertySymbol: FirPropertySymbol? = null
-
     override val controlFlowGraphReference: FirControlFlowGraphReference? = null
 
     override val contractDescription: FirContractDescription = FirEmptyContractDescription

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/synthetic/FirSyntheticPropertyBuilder.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2022 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.
  */
 
@@ -27,8 +27,8 @@ class FirSyntheticPropertyBuilder {
         moduleData, name, isVar = delegateSetter != null, symbol = symbol,
         status = status ?: delegateGetter.status,
         resolvePhase = delegateGetter.resolvePhase,
-        getter = FirSyntheticPropertyAccessor(delegateGetter, isGetter = true),
-        setter = delegateSetter?.let { FirSyntheticPropertyAccessor(it, isGetter = false) },
+        getter = FirSyntheticPropertyAccessor(delegateGetter, isGetter = true, symbol),
+        setter = delegateSetter?.let { FirSyntheticPropertyAccessor(it, isGetter = false, symbol) },
         deprecationsProvider = deprecationsProvider
     )
 }

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/NodeConfigurator.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2022 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.
  */
 
@@ -337,7 +337,7 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
 
         propertyAccessor.configure {
             +symbol("FirPropertyAccessorSymbol")
-            +field("propertySymbol", firPropertySymbolType, nullable = true).apply {
+            +field("propertySymbol", firPropertySymbolType).apply {
                 withBindThis = false
             }
             +booleanField("isGetter")