Registering field trial for a feature overridden in chrome://flags.

components/flags_ui/flags_state_unittest.cc

Index: components/flags_ui/flags_state_unittest.cc
diff --git a/components/flags_ui/flags_state_unittest.cc b/components/flags_ui/flags_state_unittest.cc
index b95373a5f4ba8775df577b6b104c9dd971de43c7..990e136e023d5f3cfc57979d796a20b57c7ed49a 100644
--- a/components/flags_ui/flags_state_unittest.cc
+++ b/components/flags_ui/flags_state_unittest.cc
@@ -268,10 +268,13 @@ TEST_F(FlagsStateTest, ConvertFlagsToSwitches) {
 
 TEST_F(FlagsStateTest, RegisterAllFeatureVariationParameters) {
   const FeatureEntry& entry = kEntries[7];
+  std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
+
   // Select the "Disabled" variation.
   flags_state_->SetFeatureEntryEnabled(&flags_storage_, entry.NameForOption(0),
                                        true);
-  flags_state_->RegisterAllFeatureVariationParameters(&flags_storage_);
+  flags_state_->RegisterAllFeatureVariationParameters(&flags_storage_,
+                                                      feature_list.get());
   // No value should be associated.
   EXPECT_EQ("", variations::GetVariationParamValue(kTestTrial, kTestParam));
   // The trial should not be created.
@@ -282,10 +285,19 @@ TEST_F(FlagsStateTest, RegisterAllFeatureVariationParameters) {
   flags_state_->SetFeatureEntryEnabled(&flags_storage_, entry.NameForOption(1),
                                        true);
 
-  flags_state_->RegisterAllFeatureVariationParameters(&flags_storage_);
+  flags_state_->RegisterAllFeatureVariationParameters(&flags_storage_,
+                                                      feature_list.get());
+  // Set the feature_list as the main instance so that
+  // variations::GetVariationParamValueByFeature below works.
+  base::FeatureList::ClearInstanceForTesting();
+  base::FeatureList::SetInstance(std::move(feature_list));
+
   // The value should be associated.
   EXPECT_EQ(kTestParamValue1,
             variations::GetVariationParamValue(kTestTrial, kTestParam));
+  // The value should be associated also via the name of the feature.
+  EXPECT_EQ(kTestParamValue1, variations::GetVariationParamValueByFeature(
+                                  kTestFeature2, kTestParam));
 
   // The trial should be created.
   trial = base::FieldTrialList::Find(kTestTrial);
@@ -296,7 +308,8 @@ TEST_F(FlagsStateTest, RegisterAllFeatureVariationParameters) {
   // Select the second "Enabled" variation.
   flags_state_->SetFeatureEntryEnabled(&flags_storage_, entry.NameForOption(2),
                                        true);
-  flags_state_->RegisterAllFeatureVariationParameters(&flags_storage_);
+  flags_state_->RegisterAllFeatureVariationParameters(&flags_storage_,
+                                                      feature_list.get());
   // Associating for the second time should not change the value.
   EXPECT_EQ(kTestParamValue1,
             variations::GetVariationParamValue(kTestTrial, kTestParam));