[LibFuzzer] Unbreak the `trace-malloc-unbalanced.test` when using Python 3.

[delcypher]

Summary

[LibFuzzer] Unbreak the trace-malloc-unbalanced.test when using Python 3.

The unbalanced_allocs.py script uses Python 2 print statement
and iteritems(). Running 2to3 over the script fixes these.

[kcc]

LGTM

lib/fuzzer/scripts/unbalanced_allocs.py

 import sys
 
 _skip = 0
 
 def PrintStack(line, stack):
   global _skip
   if _skip > 0:
     return
-  print 'Unbalanced ' + line.rstrip();
+  print('Unbalanced ' + line.rstrip());
   for l in stack:
-    print l.rstrip()
+    print(l.rstrip())
 
 def ProcessStack(line, f):
   stack = []
   while line and line.startswith('    #'):
     stack += [line]
     line = f.readline()
   return line, stack
 
def ProcessMalloc(line, f, allocs):
   allocs[addr] = (line, stack)
   return next_line
 
 def ProcessRun(line, f):
   if not line.startswith('MallocFreeTracer: START'):
     return ProcessMalloc(line, f, {})
 
   allocs = {}
-  print line.rstrip()
+  print(line.rstrip())
   line = f.readline()
   while line:
     if line.startswith('MallocFreeTracer: STOP'):
       global _skip
       _skip = _skip - 1
-      for _, (l, s) in allocs.iteritems():
+      for _, (l, s) in allocs.items():
         PrintStack(l, s)
-      print line.rstrip()
+      print(line.rstrip())
       return f.readline()
     line = ProcessMalloc(line, f, allocs)
   return line
 
 def ProcessFile(f):
   line = f.readline()
   while line:
     line = ProcessRun(line, f);