[Python] Implement __next__ for value_iter

Python 3 iteration calls the next() method instead of next() and
value_iter only implemented the Python 2 version.

Differential revision: https://reviews.llvm.org/D67184

llvm-svn: 370954
(cherry picked from commit 6eef8e0)

Author: JDevlieghere

lldb/packages/Python/lldbsuite/test/python_api/value/TestValueAPI.py

@@ -169,6 +169,13 @@ def test(self):
         self.assertTrue(int(lldb.value(frame0.FindVariable('sinthex')))
                         == -526164208, 'sinthex == -526164208')
 
+        # Check value_iter works correctly.
+        for v in [
+                lldb.value(frame0.FindVariable('uinthex')),
+                lldb.value(frame0.FindVariable('sinthex'))
+        ]:
+            self.assertTrue(v)
+
         self.assertTrue(
             frame0.FindVariable('uinthex').GetValueAsUnsigned() == 3768803088,
             'unsigned uinthex == 3768803088')

lldb/scripts/Python/python-extensions.swig

@@ -946,13 +946,16 @@ class value_iter(object):
     def __iter__(self):
         return self
 
-    def next(self):
+    def __next__(self):
         if self.index >= self.length:
             raise StopIteration()
         child_sbvalue = self.sbvalue.GetChildAtIndex(self.index)
         self.index += 1
         return value(child_sbvalue)
 
+    def next(self):
+        return self.__next__()
+
     def __init__(self,value):
         self.index = 0
         self.sbvalue = value