[FIR2IR] Generate IR declarations in classes in strict order

Order is following:
- declared declarations in declaration (in source) order
- generated declarations in sorted order

compiler/testData/ir/irText/classes/declarationOrder.ir.txt

@@ -0,0 +1,84 @@
+FILE fqName:test fileName:/declarationOrder.kt
+  CLASS CLASS name:A modality:FINAL visibility:public superTypes:[kotlin.Any]
+    $this: VALUE_PARAMETER INSTANCE_RECEIVER name:<this> type:test.A
+    CONSTRUCTOR visibility:public <> () returnType:test.A [primary]
+      BLOCK_BODY
+        DELEGATING_CONSTRUCTOR_CALL 'public constructor <init> () [primary] declared in kotlin.Any'
+        INSTANCE_INITIALIZER_CALL classDescriptor='CLASS CLASS name:A modality:FINAL visibility:public superTypes:[kotlin.Any]'
+    CONSTRUCTOR visibility:public <> (x:kotlin.Int) returnType:test.A
+      VALUE_PARAMETER name:x index:0 type:kotlin.Int
+      BLOCK_BODY
+        DELEGATING_CONSTRUCTOR_CALL 'public constructor <init> () [primary] declared in test.A'
+    FUN name:b visibility:public modality:FINAL <> ($this:test.A) returnType:kotlin.Unit
+      $this: VALUE_PARAMETER name:<this> type:test.A
+      BLOCK_BODY
+    FUN name:a visibility:public modality:FINAL <> ($this:test.A) returnType:kotlin.Unit
+      $this: VALUE_PARAMETER name:<this> type:test.A
+      BLOCK_BODY
+    PROPERTY name:b visibility:public modality:FINAL [val]
+      FIELD PROPERTY_BACKING_FIELD name:b type:kotlin.Int visibility:private [final]
+        EXPRESSION_BODY
+          CONST Int type=kotlin.Int value=1
+      FUN DEFAULT_PROPERTY_ACCESSOR name:<get-b> visibility:public modality:FINAL <> ($this:test.A) returnType:kotlin.Int
+        correspondingProperty: PROPERTY name:b visibility:public modality:FINAL [val]
+        $this: VALUE_PARAMETER name:<this> type:test.A
+        BLOCK_BODY
+          RETURN type=kotlin.Nothing from='public final fun <get-b> (): kotlin.Int declared in test.A'
+            GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:b type:kotlin.Int visibility:private [final]' type=kotlin.Int origin=null
+              receiver: GET_VAR '<this>: test.A declared in test.A.<get-b>' type=test.A origin=null
+    PROPERTY name:a visibility:public modality:FINAL [val]
+      FIELD PROPERTY_BACKING_FIELD name:a type:kotlin.Int visibility:private [final]
+        EXPRESSION_BODY
+          CONST Int type=kotlin.Int value=2
+      FUN DEFAULT_PROPERTY_ACCESSOR name:<get-a> visibility:public modality:FINAL <> ($this:test.A) returnType:kotlin.Int
+        correspondingProperty: PROPERTY name:a visibility:public modality:FINAL [val]
+        $this: VALUE_PARAMETER name:<this> type:test.A
+        BLOCK_BODY
+          RETURN type=kotlin.Nothing from='public final fun <get-a> (): kotlin.Int declared in test.A'
+            GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:a type:kotlin.Int visibility:private [final]' type=kotlin.Int origin=null
+              receiver: GET_VAR '<this>: test.A declared in test.A.<get-a>' type=test.A origin=null
+    CONSTRUCTOR visibility:public <> (x:kotlin.String) returnType:test.A
+      VALUE_PARAMETER name:x index:0 type:kotlin.String
+      BLOCK_BODY
+        DELEGATING_CONSTRUCTOR_CALL 'public constructor <init> () [primary] declared in test.A'
+    PROPERTY name:b visibility:public modality:FINAL [val]
+      FUN name:<get-b> visibility:public modality:FINAL <> ($this:test.A, $receiver:kotlin.Int) returnType:kotlin.String
+        correspondingProperty: PROPERTY name:b visibility:public modality:FINAL [val]
+        $this: VALUE_PARAMETER name:<this> type:test.A
+        $receiver: VALUE_PARAMETER name:<this> type:kotlin.Int
+        BLOCK_BODY
+          RETURN type=kotlin.Nothing from='public final fun <get-b> (): kotlin.String declared in test.A'
+            CONST String type=kotlin.String value="b"
+    FUN name:b visibility:public modality:FINAL <> ($this:test.A, $receiver:kotlin.String) returnType:kotlin.Unit
+      $this: VALUE_PARAMETER name:<this> type:test.A
+      $receiver: VALUE_PARAMETER name:<this> type:kotlin.String
+      BLOCK_BODY
+    PROPERTY name:a visibility:public modality:FINAL [val]
+      FUN name:<get-a> visibility:public modality:FINAL <> ($this:test.A, $receiver:kotlin.Int) returnType:kotlin.String
+        correspondingProperty: PROPERTY name:a visibility:public modality:FINAL [val]
+        $this: VALUE_PARAMETER name:<this> type:test.A
+        $receiver: VALUE_PARAMETER name:<this> type:kotlin.Int
+        BLOCK_BODY
+          RETURN type=kotlin.Nothing from='public final fun <get-a> (): kotlin.String declared in test.A'
+            CONST String type=kotlin.String value="a"
+    FUN name:a visibility:public modality:FINAL <> ($this:test.A, $receiver:kotlin.String) returnType:kotlin.Unit
+      $this: VALUE_PARAMETER name:<this> type:test.A
+      $receiver: VALUE_PARAMETER name:<this> type:kotlin.String
+      BLOCK_BODY
+    CONSTRUCTOR visibility:public <> (x:kotlin.Double) returnType:test.A
+      VALUE_PARAMETER name:x index:0 type:kotlin.Double
+      BLOCK_BODY
+        DELEGATING_CONSTRUCTOR_CALL 'public constructor <init> () [primary] declared in test.A'
+    FUN FAKE_OVERRIDE name:equals visibility:public modality:OPEN <> ($this:kotlin.Any, other:kotlin.Any?) returnType:kotlin.Boolean [fake_override,operator]
+      overridden:
+        public open fun equals (other: kotlin.Any?): kotlin.Boolean [operator] declared in kotlin.Any
+      $this: VALUE_PARAMETER name:<this> type:kotlin.Any
+      VALUE_PARAMETER name:other index:0 type:kotlin.Any?
+    FUN FAKE_OVERRIDE name:hashCode visibility:public modality:OPEN <> ($this:kotlin.Any) returnType:kotlin.Int [fake_override]
+      overridden:
+        public open fun hashCode (): kotlin.Int declared in kotlin.Any
+      $this: VALUE_PARAMETER name:<this> type:kotlin.Any
+    FUN FAKE_OVERRIDE name:toString visibility:public modality:OPEN <> ($this:kotlin.Any) returnType:kotlin.String [fake_override]
+      overridden:
+        public open fun toString (): kotlin.String declared in kotlin.Any
+      $this: VALUE_PARAMETER name:<this> type:kotlin.Any

compiler/testData/ir/irText/classes/declarationOrder.kt

@@ -0,0 +1,19 @@
+// FIR_IDENTICAL
+// SKIP_KLIB_TEST
+// IGNORE_BACKEND_K1: JS_IR
+//   Ignore reason: there is a js name clash between function `a()` and property `a`
+package test
+
+class A() {
+    constructor(x: Int) : this()
+    fun b() {}
+    fun a() {}
+    val b: Int = 1
+    val a: Int = 2
+    constructor(x: String) : this()
+    val Int.b: String get() = "b"
+    fun String.b() {}
+    val Int.a: String get() = "a"
+    fun String.a() {}
+    constructor(x: Double) : this()
+}

compiler/testData/ir/irText/classes/declarationOrder.kt.txt

@@ -0,0 +1,53 @@
+package test
+
+class A {
+  constructor() /* primary */ {
+    super/*Any*/()
+    /* <init>() */
+
+  }
+
+  constructor(x: Int) {
+    this/*A*/()
+  }
+
+  fun b() {
+  }
+
+  fun a() {
+  }
+
+  val b: Int
+    field = 1
+    get
+
+  val a: Int
+    field = 2
+    get
+
+  constructor(x: String) {
+    this/*A*/()
+  }
+
+  val Int.b: String
+    get(): String {
+      return "b"
+    }
+
+  fun String.b() {
+  }
+
+  val Int.a: String
+    get(): String {
+      return "a"
+    }
+
+  fun String.a() {
+  }
+
+  constructor(x: Double) {
+    this/*A*/()
+  }
+
+}
+