Add variations filtering for is_low_end_device.

components/variations/study_filtering_unittest.cc

Index: components/variations/study_filtering_unittest.cc
diff --git a/components/variations/study_filtering_unittest.cc b/components/variations/study_filtering_unittest.cc
index 1d70c48c8cf04ef5f78ca8781f783a95dfb375c6..18f2593d7c8cb6cfd6112fd424f71dff10c28fe2 100644
--- a/components/variations/study_filtering_unittest.cc
+++ b/components/variations/study_filtering_unittest.cc
@@ -255,6 +255,22 @@ TEST(VariationsStudyFilteringTest, CheckStudyPlatform) {
   }
 }
 
+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);