Add variations filtering for is_low_end_device.

components/variations/study_filtering_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/variations/study_filtering.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
 
@@ skipping 237 matching lines @@
     }
 
     if (i < arraysize(platforms)) {
       const int index = arraysize(platforms) - i - 1;
       filter.add_platform(platforms[index]);
       platform_added[index] = true;
     }
   }
 }
 
+TEST(VariationsStudyFilteringTest, CheckStudyLowEndDevice) {
+  Study::Filter filter;
+
+  // Check that if the filter is not set, study applies to either low end.

[rkaplow, 2017/07/06 17:49:49]

nit - "either low end setting"? Current wording seems awkward

[Alexei Svitkine (slow), 2017/07/11 15:08:14]

Done.

+  EXPECT_TRUE(internal::CheckStudyLowEndDevice(filter, true));
+  EXPECT_TRUE(internal::CheckStudyLowEndDevice(filter, false));
+
+  filter.set_is_low_end_device(true);
+  EXPECT_TRUE(internal::CheckStudyLowEndDevice(filter, true));
+  EXPECT_FALSE(internal::CheckStudyLowEndDevice(filter, false));
+
+  filter.set_is_low_end_device(false);
+  EXPECT_FALSE(internal::CheckStudyLowEndDevice(filter, true));
+  EXPECT_TRUE(internal::CheckStudyLowEndDevice(filter, false));
+}
+
 TEST(VariationsStudyFilteringTest, CheckStudyStartDate) {
   const base::Time now = base::Time::Now();
   const base::TimeDelta delta = base::TimeDelta::FromHours(1);
   const struct {
     const base::Time start_date;
     bool expected_result;
   } start_test_cases[] = {
       {now - delta, true},
       // Note, the proto start_date is truncated to seconds, but the reference
       // date isn't.
@@ skipping 412 matching lines @@
 
   default_group->set_name("def");
   EXPECT_TRUE(processed_study.Init(&study, false));
   Study::Experiment* repeated_group = study.add_experiment();
   repeated_group->set_name("abc");
   repeated_group->set_probability_weight(1);
   EXPECT_FALSE(processed_study.Init(&study, false));
 }
 
 }  // namespace variations