Create ast/ and parsing/ subdirectories and move appropriate files

src/ast/ast-literal-reindexer.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef V8_AST_LITERAL_REINDEXER
-#define V8_AST_LITERAL_REINDEXER
+#ifndef V8_AST_AST_LITERAL_REINDEXER
+#define V8_AST_AST_LITERAL_REINDEXER
 
-#include "src/ast.h"
-#include "src/scopes.h"
+#include "src/ast/ast.h"
+#include "src/ast/scopes.h"
 
 namespace v8 {
 namespace internal {
 
 class AstLiteralReindexer final : public AstVisitor {
  public:
   AstLiteralReindexer() : AstVisitor(), next_index_(0) {}
 
   int count() const { return next_index_; }
   void Reindex(Expression* pattern);
@@ skipping 15 matching lines @@
 
   void Visit(AstNode* node) override { node->Accept(this); }
 
   int next_index_;
 
   DISALLOW_COPY_AND_ASSIGN(AstLiteralReindexer);
 };
 }  // namespace internal
 }  // namespace v8
 
-#endif  // V8_AST_LITERAL_REINDEXER
+#endif  // V8_AST_AST_LITERAL_REINDEXER