gn: handle continued suffix comments

tools/gn/parse_tree.h

 // Copyright (c) 2013 The Chromium 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 TOOLS_GN_PARSE_TREE_H_
 #define TOOLS_GN_PARSE_TREE_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 21 matching lines @@
 
   const std::vector<Token>& before() const { return before_; }
   void append_before(Token c) {
     before_.push_back(c);
   }
 
   const std::vector<Token>& suffix() const { return suffix_; }
   void append_suffix(Token c) {
     suffix_.push_back(c);
   }
+  // Reverse the order of the suffix comments. When walking the tree in
+  // post-order we append suffix comments in reverse order, so this fixes them
+  // up.
+  void ReverseSuffix();
 
   const std::vector<Token>& after() const { return after_; }
   void append_after(Token c) {
     after_.push_back(c);
   }
 
  private:
   // Whole line comments before the expression.
   std::vector<Token> before_;
 
@@ skipping 376 matching lines @@
   }
 
  private:
   Token op_;
   scoped_ptr<ParseNode> operand_;
 
   DISALLOW_COPY_AND_ASSIGN(UnaryOpNode);
 };
 
 #endif  // TOOLS_GN_PARSE_TREE_H_