Reland of Use the crrev recipe module to fetch commit hashes.

scripts/slave/recipes/bisect_test/example_bisect_results.py

Index: scripts/slave/recipes/bisect_test/example_bisect_results.py
diff --git a/scripts/slave/recipes/bisect_test/example_bisect_results.py b/scripts/slave/recipes/bisect_test/example_bisect_results.py
index 3be8ddca28bc9d36c9a97683ef828ab8e1fdff5a..2d82607a6b38b122af84b7260403bea41d3e47c8 100644
--- a/scripts/slave/recipes/bisect_test/example_bisect_results.py
+++ b/scripts/slave/recipes/bisect_test/example_bisect_results.py
@@ -91,9 +91,11 @@ def set_attributes(target, attributes):
 
 
 def add_revision_mapping(api, test, pos, sha):
-  step_name = 'Resolving reference range.resolving commit_pos ' + pos
-  stdout = api.raw_io.output('hash:' + sha)
+  step_name = ('Resolving reference range.crrev get commit hash for ' +
+               'refs/heads/master@{#%s}' % pos)
+  stdout = api.json.output({'git_sha': sha})
   test += api.step_data(step_name, stdout=stdout)
+
   step_name = 'Resolving reference range.resolving hash ' + sha
   pos = 'refs/heads/master@{#%s}' % pos
   stdout = api.raw_io.output(pos)