json_schema_compiler: Use NumberToString instead of IntToString

IntToString has been deprecated in favour of NumberToString.
Using NumberToString also fixes a few 64-bit truncation warnings.

Bug: 879657
Change-Id: Icd305fbc7ee005df63271a74412eb6dffad19712
Reviewed-on: https://chromium-review.googlesource.com/c/1448463
Auto-Submit: Raul Tambre <raul@tambre.ee>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#628413}

tools/json_schema_compiler/cc_generator.py

@@ -670,7 +670,7 @@ class _Generator(object):
           ' || %(var)s.GetSize() > %(total)d) {')
     (c.Concat(self._GenerateError(
         '"expected %%(total)d arguments, got " '
-        '+ base::IntToString(%%(var)s.GetSize())'))
+        '+ base::NumberToString(%%(var)s.GetSize())'))
       .Append('return nullptr;')
       .Eblock('}')
       .Substitute({