JSSpecCompiler: Add stubs for AST types

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Forward.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2023, Dan Klishch <danilklishch@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Forward.h>
+
+namespace JSSpecCompiler {
+
+// AST/AST.h
+class NodeSubtreePointer;
+
+class Node;
+using NullableTree = RefPtr<Node>;
+using Tree = NonnullRefPtr<Node>;
+class ErrorNode;
+
+class ScopedBlock;
+class MathematicalConstant;
+class StringLiteral;
+class BinaryOperation;
+class UnaryOperation;
+class IsOneOfOperation;
+class UnresolvedReference;
+class ReturnExpression;
+class AssertExpression;
+class IfBranch;
+class ElseIfBranch;
+class TreeList;
+class RecordDirectListInitialization;
+class FunctionCall;
+class SlotName;
+class Variable;
+class FunctionPointer;
+
+}