Make the gdb Vector pretty-printer work with Python version >= 3.

third_party/WebKit/Tools/gdb/webkit.py

 # Copyright (C) 2010, Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 307 matching lines @@
 
     class Iterator:
         def __init__(self, start, finish):
             self.item = start
             self.finish = finish
             self.count = 0
 
         def __iter__(self):
             return self
 
-        def next(self):
+        def __next__(self):
             if self.item == self.finish:
                 raise StopIteration
             count = self.count
             self.count += 1
             element = self.item.dereference()
             self.item += 1
             return ('[%d]' % count, element)
 
+        # Python version < 3 compatibility:
+        def next(self):
+            return self.__next__()
+
     def __init__(self, val):
         self.val = val
 
     def children(self):
         start = self.val['m_buffer']
         return self.Iterator(start, start + self.val['m_size'])
 
     def to_string(self):
         return ('%s of length %d, capacity %d'
                 % ('WTF::Vector', self.val['m_size'], self.val['m_capacity']))
@@ skipping 107 matching lines @@
             padding = ''
             while len(stack) > 0:
                 pair = stack.pop()
                 print(padding, pair[1], pair[0])
                 padding = padding + '  '
         else:
             print('Sorry: I don\'t know how to deal with %s yet.' % target_type)
 
 
 PrintPathToRootCommand()