FIR: introduce FirLazyBlock node

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

@@ -47,8 +47,8 @@ object FieldSets {
     fun symbol(symbolClassName: String, argument: String? = null): Field =
         symbolWithPackage("fir.symbols.impl", symbolClassName, argument)
 
-    fun body(nullable: Boolean = false) =
-        field("body", block, nullable)
+    fun body(nullable: Boolean = false, withReplace: Boolean = false) =
+        field("body", block, nullable, withReplace = withReplace)
 
     val returnTypeRef =
         field("returnTypeRef", typeRef)

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

@@ -113,6 +113,23 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             publicImplementation()
         }
 
+        impl(block, "FirLazyBlock") {
+            val error = """error("FirLazyBlock should be calculated before accessing")"""
+            default("statements") {
+                value = error
+                withGetter = true
+            }
+            default("annotations") {
+                value = error
+                withGetter = true
+            }
+            default("typeRef") {
+                value = error
+                withGetter = true
+            }
+            publicImplementation()
+        }
+
         impl(errorLoop) {
             default("block", "FirEmptyExpressionBlock()")
             default("condition", "FirErrorExpressionImpl(source, ConeStubDiagnostic(diagnostic))")

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

@@ -102,7 +102,7 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
             parentArg(callableDeclaration, "F", "F")
             +symbol("FirFunctionSymbol", "F")
             +fieldList(valueParameter, withReplace = true).withTransform()
-            +body(nullable = true).withTransform()
+            +body(nullable = true, withReplace = true).withTransform()
         }
 
         errorFunction.configure {