rebaseline_server: cache results in long-running ImageDiffDB instance

gm/rebaseline_server/compare_to_expectations_test.py

 #!/usr/bin/python
 
 """
 Copyright 2013 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 
 Test compare_to_expectations.py
 
 TODO(epoger): Create a command to update the expected results (in
 self._output_dir_expected) when appropriate.  For now, you should:
 1. examine the results in self._output_dir_actual and make sure they are ok
 2. rm -rf self._output_dir_expected
 3. mv self._output_dir_actual self._output_dir_expected
 Although, if you're using an SVN checkout, this will blow away .svn directories
 within self._output_dir_expected, which wouldn't be good...
 
 """
 
 import os
-import sys
 
 # Imports from within Skia
 import base_unittest
 import compare_to_expectations
+import imagediffdb
 import results
 import gm_json  # must import results first, so that gm_json will be in sys.path
 
 
 class CompareToExpectationsTest(base_unittest.TestCase):
 
   def test_gm(self):
     """Process results of a GM run with the ExpectationComparisons object."""
+    image_diff_db = imagediffdb.ImageDiffDB(storage_root=self._temp_dir)
     results_obj = compare_to_expectations.ExpectationComparisons(
+        image_diff_db=image_diff_db,
         actuals_root=os.path.join(self._input_dir, 'gm-actuals'),
         expected_root=os.path.join(self._input_dir, 'gm-expectations'),
-        generated_images_root=self._temp_dir,
         diff_base_url='/static/generated-images')
     results_obj.get_timestamp = mock_get_timestamp
     gm_json.WriteToFile(
         results_obj.get_packaged_results_of_type(
             results.KEY__HEADER__RESULTS_ALL),
         os.path.join(self._output_dir_actual, 'gm.json'))
 
 
 def mock_get_timestamp():
   """Mock version of BaseComparisons.get_timestamp() for testing."""
   return 12345678
 
 
 def main():
   base_unittest.main(CompareToExpectationsTest)
 
 
 if __name__ == '__main__':
   main()