Revert of Supporting study definitions without default groups and end_date filtering.

components/variations/variations_seed_processor_unittest.cc

 // Copyright 2013 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/variations_seed_processor.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <map>
@@ skipping 360 matching lines @@
   EXPECT_TRUE(processed_study.Init(&study, false));
 
   // Max version checks.
   study.mutable_filter()->set_max_version("2.3.4.*");
   EXPECT_TRUE(processed_study.Init(&study, false));
   study.mutable_filter()->set_max_version("*.3");
   EXPECT_FALSE(processed_study.Init(&study, false));
   study.mutable_filter()->set_max_version("2.3.4");
   EXPECT_TRUE(processed_study.Init(&study, false));
 
-  // A blank default study is allowed.
   study.clear_default_experiment_name();
-  EXPECT_TRUE(processed_study.Init(&study, false));
+  EXPECT_FALSE(processed_study.Init(&study, false));
 
   study.set_default_experiment_name("xyz");
   EXPECT_FALSE(processed_study.Init(&study, false));
 
   study.set_default_experiment_name("def");
   default_group->clear_name();
   EXPECT_FALSE(processed_study.Init(&study, false));
 
   default_group->set_name("def");
   EXPECT_TRUE(processed_study.Init(&study, false));
@@ skipping 445 matching lines @@
     EXPECT_TRUE(CreateTrialFromStudyWithFeatureList(study, feature_list.get()));
     base::test::ScopedFeatureList scoped_feature_list;
     scoped_feature_list.InitWithFeatureList(std::move(feature_list));
 
     // Tthe feature should not be enabled, because the study is expired.
     EXPECT_EQ(test_case.expected_feature_enabled,
               base::FeatureList::IsEnabled(test_case.feature));
   }
 }
 
-TEST_F(VariationsSeedProcessorTest, NoDefaultExperiment) {
-  base::FieldTrialList field_trial_list(nullptr);
-
-  Study study;
-  study.set_name("Study1");
-
-  AddExperiment("A", 1, &study);
-
-  EXPECT_TRUE(CreateTrialFromStudy(study));
-
-  base::FieldTrial* trial = base::FieldTrialList::Find("Study1");
-  trial->Disable();
-
-  EXPECT_EQ(ProcessedStudy::kGenericDefaultExperimentName,
-            base::FieldTrialList::FindFullName("Study1"));
-}
-
 TEST_F(VariationsSeedProcessorTest, LowEntropyStudyTest) {
   const std::string kTrial1Name = "A";
   const std::string kTrial2Name = "B";
   const std::string kGroup1Name = "AA";
   const std::string kDefaultName = "Default";
 
   VariationsSeed seed;
   Study* study1 = seed.add_study();
   study1->set_name(kTrial1Name);
   study1->set_consistency(variations::Study_Consistency_PERMANENT);
@@ skipping 26 matching lines @@
   // Since no experiment in study1 sends experiment IDs, it will use the high
   // entropy provider, which selects the non-default group.
   EXPECT_EQ(kGroup1Name, base::FieldTrialList::FindFullName(kTrial1Name));
 
   // Since an experiment in study2 has google_web_experiment_id set, it will use
   // the low entropy provider, which selects the default group.
   EXPECT_EQ(kDefaultName, base::FieldTrialList::FindFullName(kTrial2Name));
 }
 
 }  // namespace variations