Add non-host functionality to the previews blacklist

components/previews/core/previews_black_list_unittest.cc

 // Copyright 2016 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/previews/core/previews_black_list.h"
 
 #include <memory>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 16 matching lines @@
 namespace {
 
 using PreviewsBlackListTest = testing::Test;
 
 }  // namespace
 
 namespace previews {
 
 namespace {
 
-void RunLoadCallback(LoadBlackListCallback callback,
-                     std::unique_ptr<BlackListItemMap> black_list_item_map) {
-  callback.Run(std::move(black_list_item_map));
+void RunLoadCallback(
+    LoadBlackListCallback callback,
+    std::unique_ptr<BlackListItemMap> black_list_item_map,
+    std::unique_ptr<PreviewsBlackListItem> host_indifferent_black_list_item) {
+  callback.Run(std::move(black_list_item_map),
+               std::move(host_indifferent_black_list_item));
 }
 
 class TestPreviewsOptOutStore : public PreviewsOptOutStore {
  public:
   TestPreviewsOptOutStore() : clear_blacklist_count_(0) {}
   ~TestPreviewsOptOutStore() override {}
 
   int clear_blacklist_count() { return clear_blacklist_count_; }
 
  private:
   // PreviewsOptOutStore implementation:
   void AddPreviewNavigation(bool opt_out,
                             const std::string& host_name,
                             PreviewsType type,
                             base::Time now) override {}
 
   void LoadBlackList(LoadBlackListCallback callback) override {
     std::unique_ptr<BlackListItemMap> black_list_item_map(
         new BlackListItemMap());
+    std::unique_ptr<PreviewsBlackListItem> host_indifferent_black_list_item =
+        PreviewsBlackList::CreateHostIndifferentBlackListItem();
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&RunLoadCallback, callback,
-                              base::Passed(&black_list_item_map)));
+                              base::Passed(&black_list_item_map),
+                              base::Passed(&host_indifferent_black_list_item)));
   }
 
   void ClearBlackList(base::Time begin_time, base::Time end_time) override {
     ++clear_blacklist_count_;
   }
 
   int clear_blacklist_count_;
 };
 
 }  // namespace
 
-TEST_F(PreviewsBlackListTest, BlackListNoStore) {
+TEST_F(PreviewsBlackListTest, PerHostBlackListNoStore) {
   // Tests the black list behavior when a null OptOutSture is passed in.
   const GURL url_a("http://www.url_a.com");
   const GURL url_b("http://www.url_b.com");
-  const size_t history = 4;
-  const int threshold = 2;
+  const size_t per_host_history = 4;
+  const int per_host_threshold = 2;
+  // Host indifferent blacklisting should have no effect with the following
+  // params.
+  const size_t host_indifferent_history = 1;
+  const int host_indifferent_threshold = 2;

[tbansal1, 2016/10/28 21:59:33]

s/2/host_indifferent_history + 1/
Also, why are some size_t, others int?

here and below.

[RyanSturm, 2016/11/02 19:52:30]

Done.

size_t is used here for the actual size of a collection, whereas the ints are
used internally for counts. Open a bug on it if you want it fixed throughout the
blacklist. I don't think it's a problem.

   const int duration_in_days = 365;
   // Disable single opt out by setting duration to 0.
   const int single_opt_out_duration = 0;
   base::FieldTrialList field_trial_list(nullptr);
   std::map<std::string, std::string> params;
-  params["stored_history_length"] = base::SizeTToString(history);
-  params["opt_out_threshold"] = base::IntToString(threshold);
-  params["black_list_duration_in_days"] = base::IntToString(duration_in_days);
+  params["per_host_max_stored_history_length"] =
+      base::SizeTToString(per_host_history);
+  params["host_indifferent_max_stored_history_length"] =
+      base::SizeTToString(host_indifferent_history);
+  params["per_host_opt_out_threshold"] = base::IntToString(per_host_threshold);
+  params["host_indifferent_opt_out_threshold"] =
+      base::IntToString(host_indifferent_threshold);
+  params["per_host_black_list_duration_in_days"] =
+      base::IntToString(duration_in_days);
   params["single_opt_out_duration_in_seconds"] =
       base::IntToString(single_opt_out_duration);
   ASSERT_TRUE(
       variations::AssociateVariationParams("ClientSidePreviews", "Enabled",
                                            params) &&
       base::FieldTrialList::CreateFieldTrial("ClientSidePreviews", "Enabled"));
 
   base::SimpleTestClock* test_clock = new base::SimpleTestClock();
   base::Time start = test_clock->Now();
   test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   std::unique_ptr<PreviewsBlackList> black_list(
       new PreviewsBlackList(nullptr, base::WrapUnique(test_clock)));
 
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   black_list->AddPreviewNavigation(url_a, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_a, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   black_list->AddPreviewNavigation(url_b, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_b, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   black_list->AddPreviewNavigation(url_b, false, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_b, false, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_b, false, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
-  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->ClearBlackList(start, test_clock->Now());
 
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   variations::testing::ClearAllVariationParams();
 }
 
-TEST_F(PreviewsBlackListTest, BlackListWithStore) {
+TEST_F(PreviewsBlackListTest, PerHostBlackListWithStore) {
   // Tests the black list behavior when a non-null OptOutSture is passed in.
   const GURL url_a1("http://www.url_a.com/a1");
   const GURL url_a2("http://www.url_a.com/a2");
   const GURL url_b("http://www.url_b.com");
-  const size_t history = 4;
-  const int threshold = 2;
+  const size_t per_host_history = 4;
+  const int per_host_threshold = 2;
+  // Host indifferent blacklisting should have no effect with the following
+  // params.
+  const size_t host_indifferent_history = 1;
+  const int host_indifferent_threshold = 2;
   const int duration_in_days = 365;
   // Disable single opt out by setting duration to 0.
   const int single_opt_out_duration = 0;
   base::FieldTrialList field_trial_list(nullptr);
   std::map<std::string, std::string> params;
-  params["stored_history_length"] = base::SizeTToString(history);
-  params["opt_out_threshold"] = base::IntToString(threshold);
-  params["black_list_duration_in_days"] = base::IntToString(duration_in_days);
+  params["per_host_max_stored_history_length"] =
+      base::SizeTToString(per_host_history);
+  params["host_indifferent_max_stored_history_length"] =
+      base::SizeTToString(host_indifferent_history);
+  params["per_host_opt_out_threshold"] = base::IntToString(per_host_threshold);
+  params["host_indifferent_opt_out_threshold"] =
+      base::IntToString(host_indifferent_threshold);
+  params["per_host_black_list_duration_in_days"] =
+      base::IntToString(duration_in_days);
   params["single_opt_out_duration_in_seconds"] =
       base::IntToString(single_opt_out_duration);
   ASSERT_TRUE(
       variations::AssociateVariationParams("ClientSidePreviews", "Enabled",
                                            params) &&
       base::FieldTrialList::CreateFieldTrial("ClientSidePreviews", "Enabled"));
 
   base::MessageLoop loop;
 
   base::SimpleTestClock* test_clock = new base::SimpleTestClock();
   base::Time start = test_clock->Now();
   test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   TestPreviewsOptOutStore* opt_out_store = new TestPreviewsOptOutStore();
 
   std::unique_ptr<PreviewsBlackList> black_list(new PreviewsBlackList(
       base::WrapUnique(opt_out_store), base::WrapUnique(test_clock)));
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   base::RunLoop().RunUntilIdle();
 
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   black_list->AddPreviewNavigation(url_a1, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_a1, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   black_list->AddPreviewNavigation(url_b, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_b, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   black_list->AddPreviewNavigation(url_b, false, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_b, false, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
   black_list->AddPreviewNavigation(url_b, false, PreviewsType::OFFLINE);
-
-  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
-  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
-  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
-
-  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+
+  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
+  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
+
   EXPECT_EQ(0, opt_out_store->clear_blacklist_count());
   black_list->ClearBlackList(start, base::Time::Now());
   EXPECT_EQ(1, opt_out_store->clear_blacklist_count());
 
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a2, PreviewsType::OFFLINE));
   EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(1, opt_out_store->clear_blacklist_count());
 
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a1, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
 
   variations::testing::ClearAllVariationParams();
 }
 
-TEST_F(PreviewsBlackListTest, QueueBehavior) {
-  // Tests the black list asynchronous queue behavior. Methods called while
-  // loading are queued and should run in the order they were queued.
-  const GURL url("http://www.url.com");
-  const GURL url2("http://www.url2.com");
+TEST_F(PreviewsBlackListTest, HostIndifferentBlackList) {
+  // Tests the black list behavior when a null OptOutSture is passed in.
+  const GURL url_a("http://www.url_a.com");
+  const GURL url_b("http://www.url_b.com");
+  const GURL url_c("http://www.url_c.com");
+  const GURL url_d("http://www.url_d.com");
+  // Per host blacklisting should have no effect with the following params.
+  const size_t per_host_history = 1;
+  const int per_host_threshold = 2;

[tbansal1, 2016/10/28 21:59:34]

s/2/per_host_history + 1/

[RyanSturm, 2016/11/02 19:52:30]

Done.

+  const size_t host_indifferent_history = 4;
+  const int host_indifferent_threshold = 4;
   const int duration_in_days = 365;
   // Disable single opt out by setting duration to 0.
   const int single_opt_out_duration = 0;
   base::FieldTrialList field_trial_list(nullptr);
   std::map<std::string, std::string> params;
-  params["black_list_duration_in_days"] = base::IntToString(duration_in_days);
+  params["per_host_max_stored_history_length"] =
+      base::SizeTToString(per_host_history);
+  params["host_indifferent_max_stored_history_length"] =
+      base::SizeTToString(host_indifferent_history);
+  params["per_host_opt_out_threshold"] = base::IntToString(per_host_threshold);
+  params["host_indifferent_opt_out_threshold"] =
+      base::IntToString(host_indifferent_threshold);
+  params["per_host_black_list_duration_in_days"] =
+      base::IntToString(duration_in_days);
   params["single_opt_out_duration_in_seconds"] =
       base::IntToString(single_opt_out_duration);
   ASSERT_TRUE(
       variations::AssociateVariationParams("ClientSidePreviews", "Enabled",
                                            params) &&
       base::FieldTrialList::CreateFieldTrial("ClientSidePreviews", "Enabled"));
 
+  base::SimpleTestClock* test_clock = new base::SimpleTestClock();
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+
+  std::unique_ptr<PreviewsBlackList> black_list(
+      new PreviewsBlackList(nullptr, base::WrapUnique(test_clock)));
+
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_c, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_d, PreviewsType::OFFLINE));
+
+  black_list->AddPreviewNavigation(url_a, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
+
+  black_list->AddPreviewNavigation(url_b, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
+
+  black_list->AddPreviewNavigation(url_c, true, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
+
+  black_list->AddPreviewNavigation(url_d, true, PreviewsType::OFFLINE);

[tbansal1, 2016/10/28 21:59:33]

can you put this in a loop:
for(size_t i=0; i< host_indifferent_threshold; i++) {
  black_list->AddPreviewNavigation(url[i], true, PreviewsType::OFFLINE);
  EXPECT_EQ(i!=3, black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
}

This will make it clear that 4 is linked to threshold of 4 set earlier.

[RyanSturm, 2016/11/02 19:52:30]

Done.

+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
+  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
+  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_c, PreviewsType::OFFLINE));
+  EXPECT_FALSE(black_list->IsLoadedAndAllowed(url_d, PreviewsType::OFFLINE));
+
+  black_list->AddPreviewNavigation(url_d, false, PreviewsType::OFFLINE);
+  test_clock->Advance(base::TimeDelta::FromSeconds(1));
+
+  // New non-opt-out entry will cause these to be allowed now.
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_a, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_c, PreviewsType::OFFLINE));
+  EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_d, PreviewsType::OFFLINE));
+
+  variations::testing::ClearAllVariationParams();
+}
+
+TEST_F(PreviewsBlackListTest, QueueBehavior) {
+  // Tests the black list asynchronous queue behavior. Methods called while
+  // loading are queued and should run in the order they were queued.

[tbansal1, 2016/10/28 21:59:34]

s/loading/loading opt-out store/

It is not clear what loading is here (loading webpage?)

[RyanSturm, 2016/11/02 19:52:30]

Done.

+  const GURL url("http://www.url.com");
+  const GURL url2("http://www.url2.com");
+  // Host indifferent blacklisting should have no effect with the following
+  // params.
+  const size_t host_indifferent_history = 1;
+  const int host_indifferent_threshold = 2;
+  const int duration_in_days = 365;
+  // Disable single opt out by setting duration to 0.
+  const int single_opt_out_duration = 0;
+  base::FieldTrialList field_trial_list(nullptr);
+  std::map<std::string, std::string> params;
+  params["per_host_black_list_duration_in_days"] =
+      base::IntToString(duration_in_days);
+  params["host_indifferent_max_stored_history_length"] =
+      base::SizeTToString(host_indifferent_history);
+  params["host_indifferent_opt_out_threshold"] =
+      base::IntToString(host_indifferent_threshold);
+  params["single_opt_out_duration_in_seconds"] =
+      base::IntToString(single_opt_out_duration);
+  ASSERT_TRUE(
+      variations::AssociateVariationParams("ClientSidePreviews", "Enabled",
+                                           params) &&
+      base::FieldTrialList::CreateFieldTrial("ClientSidePreviews", "Enabled"));
+
   base::MessageLoop loop;
 
   std::vector<bool> test_opt_out{true, false};
 
   for (auto opt_out : test_opt_out) {
     base::SimpleTestClock* test_clock = new base::SimpleTestClock();
+    base::Time start = test_clock->Now();
 
     TestPreviewsOptOutStore* opt_out_store = new TestPreviewsOptOutStore();
 
     std::unique_ptr<PreviewsBlackList> black_list(new PreviewsBlackList(
         base::WrapUnique(opt_out_store), base::WrapUnique(test_clock)));
 
     EXPECT_FALSE(black_list->IsLoadedAndAllowed(url, PreviewsType::OFFLINE));
     black_list->AddPreviewNavigation(url, opt_out, PreviewsType::OFFLINE);
-    black_list->AddPreviewNavigation(url, opt_out, PreviewsType::OFFLINE);
+    test_clock->Advance(base::TimeDelta::FromSeconds(1));
+    black_list->AddPreviewNavigation(url, opt_out, PreviewsType::OFFLINE);
+    test_clock->Advance(base::TimeDelta::FromSeconds(1));
     EXPECT_FALSE(black_list->IsLoadedAndAllowed(url, PreviewsType::OFFLINE));
     base::RunLoop().RunUntilIdle();
     EXPECT_EQ(!opt_out,
               black_list->IsLoadedAndAllowed(url, PreviewsType::OFFLINE));
-
-    base::Time start = test_clock->Now();
-    test_clock->Advance(base::TimeDelta::FromSeconds(1));
-    black_list->AddPreviewNavigation(url, opt_out, PreviewsType::OFFLINE);
+    black_list->AddPreviewNavigation(url, opt_out, PreviewsType::OFFLINE);
+    test_clock->Advance(base::TimeDelta::FromSeconds(1));
     black_list->AddPreviewNavigation(url, opt_out, PreviewsType::OFFLINE);
     test_clock->Advance(base::TimeDelta::FromSeconds(1));
     EXPECT_EQ(0, opt_out_store->clear_blacklist_count());
     black_list->ClearBlackList(
         start, test_clock->Now() + base::TimeDelta::FromSeconds(1));
     EXPECT_EQ(1, opt_out_store->clear_blacklist_count());
     black_list->AddPreviewNavigation(url2, opt_out, PreviewsType::OFFLINE);
+    test_clock->Advance(base::TimeDelta::FromSeconds(1));
     black_list->AddPreviewNavigation(url2, opt_out, PreviewsType::OFFLINE);
+    test_clock->Advance(base::TimeDelta::FromSeconds(1));
     base::RunLoop().RunUntilIdle();
     EXPECT_EQ(1, opt_out_store->clear_blacklist_count());
 
     EXPECT_TRUE(black_list->IsLoadedAndAllowed(url, PreviewsType::OFFLINE));
     EXPECT_EQ(!opt_out,
               black_list->IsLoadedAndAllowed(url2, PreviewsType::OFFLINE));
   }
 
   variations::testing::ClearAllVariationParams();
 }
 
 TEST_F(PreviewsBlackListTest, MaxHosts) {
   // Test that the black list only stores n hosts, and it stores the correct n
   // hosts.
   const GURL url_a("http://www.url_a.com");
   const GURL url_b("http://www.url_b.com");
   const GURL url_c("http://www.url_c.com");
   const GURL url_d("http://www.url_d.com");
   const GURL url_e("http://www.url_e.com");
   const size_t stored_history_length = 1;
   const int opt_out_threshold = 1;
   const int black_list_duration_in_days = 365;
   // Disable single opt out by setting duration to 0.
   const int single_opt_out_duration = 0;
   const size_t max_hosts_in_blacklist = 2;
+  // Host indifferent blacklisting should have no effect with the following
+  // params.
+  const size_t host_indifferent_history = 1;
+  const int host_indifferent_threshold = 2;
   base::FieldTrialList field_trial_list(nullptr);
   std::map<std::string, std::string> params;
-  params["stored_history_length"] = base::SizeTToString(stored_history_length);
-  params["opt_out_threshold"] = base::IntToString(opt_out_threshold);
-  params["black_list_duration_in_days"] =
+  params["per_host_stored_history_length"] =
+      base::SizeTToString(stored_history_length);
+  params["per_host_opt_out_threshold"] = base::IntToString(opt_out_threshold);
+  params["per_host_black_list_duration_in_days"] =
       base::IntToString(black_list_duration_in_days);
   params["max_hosts_in_blacklist"] =
       base::SizeTToString(max_hosts_in_blacklist);
+  params["host_indifferent_max_stored_history_length"] =
+      base::SizeTToString(host_indifferent_history);
+  params["host_indifferent_opt_out_threshold"] =
+      base::IntToString(host_indifferent_threshold);
   params["single_opt_out_duration_in_seconds"] =
       base::IntToString(single_opt_out_duration);
   ASSERT_TRUE(
       variations::AssociateVariationParams("ClientSidePreviews", "Enabled",
                                            params) &&
       base::FieldTrialList::CreateFieldTrial("ClientSidePreviews", "Enabled"));
 
   base::MessageLoop loop;
 
   base::SimpleTestClock* test_clock = new base::SimpleTestClock();
@@ skipping 27 matching lines @@
   // Test that when a user opts out of a preview, previews won't be shown until
   // |single_opt_out_duration| has elapsed.
   const GURL url_a("http://www.url_a.com");
   const GURL url_b("http://www.url_b.com");
   const GURL url_c("http://www.url_c.com");
   const size_t stored_history_length = 1;
   const int opt_out_threshold = 2;
   const int black_list_duration_in_days = 365;
   const int single_opt_out_duration = 5;
   const size_t max_hosts_in_blacklist = 10;
+  // Host indifferent blacklisting should have no effect with the following
+  // params.
+  const size_t host_indifferent_history = 1;
+  const int host_indifferent_threshold = 2;

[tbansal1, 2016/10/28 21:59:33]

same comment here and elsewhere:
s/2/host_indifferent_history + 1/

[RyanSturm, 2016/11/02 19:52:30]

Done.

   base::FieldTrialList field_trial_list(nullptr);
   std::map<std::string, std::string> params;
-  params["stored_history_length"] = base::SizeTToString(stored_history_length);
-  params["opt_out_threshold"] = base::IntToString(opt_out_threshold);
-  params["black_list_duration_in_days"] =
+  params["per_host_stored_history_length"] =
+      base::SizeTToString(stored_history_length);
+  params["per_host_opt_out_threshold"] = base::IntToString(opt_out_threshold);
+  params["per_host_black_list_duration_in_days"] =
       base::IntToString(black_list_duration_in_days);
   params["max_hosts_in_blacklist"] =
       base::SizeTToString(max_hosts_in_blacklist);
+  params["host_indifferent_max_stored_history_length"] =
+      base::SizeTToString(host_indifferent_history);
+  params["host_indifferent_opt_out_threshold"] =
+      base::IntToString(host_indifferent_threshold);
   params["single_opt_out_duration_in_seconds"] =
       base::IntToString(single_opt_out_duration);
   ASSERT_TRUE(
       variations::AssociateVariationParams("ClientSidePreviews", "Enabled",
                                            params) &&
       base::FieldTrialList::CreateFieldTrial("ClientSidePreviews", "Enabled"));
 
   base::SimpleTestClock* test_clock = new base::SimpleTestClock();
 
   std::unique_ptr<PreviewsBlackList> black_list(
@@ skipping 19 matching lines @@
   test_clock->Advance(
       base::TimeDelta::FromSeconds(single_opt_out_duration + 1));
 
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_b, PreviewsType::OFFLINE));
   EXPECT_TRUE(black_list->IsLoadedAndAllowed(url_c, PreviewsType::OFFLINE));
 
   variations::testing::ClearAllVariationParams();
 }
 
 }  // namespace previews