Set site engagement timestamps to privacy-respectful values when history is cleared.

chrome/browser/engagement/site_engagement_service_unittest.cc

Index: chrome/browser/engagement/site_engagement_service_unittest.cc
diff --git a/chrome/browser/engagement/site_engagement_service_unittest.cc b/chrome/browser/engagement/site_engagement_service_unittest.cc
index 29cfa2e988ce1eef0952436381408a8d2bac44e3..3436071f1c1c4b2287b7431aad6d45135810b3b8 100644
--- a/chrome/browser/engagement/site_engagement_service_unittest.cc
+++ b/chrome/browser/engagement/site_engagement_service_unittest.cc
@@ -431,20 +431,43 @@ TEST_F(SiteEngagementScoreTest, Reset) {
   current_day += base::TimeDelta::FromDays(7);
   test_clock_.SetNow(current_day);
 
-  score_.Reset(20.0);
+  score_.Reset(20.0, nullptr);
   EXPECT_DOUBLE_EQ(20.0, score_.Score());
   EXPECT_DOUBLE_EQ(0, score_.points_added_today_);
   EXPECT_EQ(current_day, score_.last_engagement_time_);
+  EXPECT_TRUE(score_.last_shortcut_launch_time_.is_null());
 
   // Adding points after the reset should work as normal.
   score_.AddPoints(5);
   EXPECT_EQ(25.0, score_.Score());
 
-  // The decay should happen one decay period from
+  // The decay should happen one decay period from the current time.
   test_clock_.SetNow(current_day +
                      base::TimeDelta::FromDays(
                          SiteEngagementScore::GetDecayPeriodInDays() + 1));
   EXPECT_EQ(25.0 - SiteEngagementScore::GetDecayPoints(), score_.Score());
+
+  // Ensure that manually setting a time works as expected.
+  score_.AddPoints(5);
+  test_clock_.SetNow(GetReferenceTime());
+  base::Time now = test_clock_.Now();
+  score_.Reset(10.0, &now);
+
+  EXPECT_DOUBLE_EQ(10.0, score_.Score());
+  EXPECT_DOUBLE_EQ(0, score_.points_added_today_);
+  EXPECT_EQ(now, score_.last_engagement_time_);
+  EXPECT_TRUE(score_.last_shortcut_launch_time_.is_null());
+
+  score_.set_last_shortcut_launch_time(test_clock_.Now());
+  test_clock_.SetNow(GetReferenceTime() + base::TimeDelta::FromDays(3));
+  now = test_clock_.Now();
+  score_.Reset(15.0, &now);
+
+  // 5 bonus from the last shortcut launch.
+  EXPECT_DOUBLE_EQ(20.0, score_.Score());
+  EXPECT_DOUBLE_EQ(0, score_.points_added_today_);
+  EXPECT_EQ(now, score_.last_engagement_time_);
+  EXPECT_EQ(now, score_.last_shortcut_launch_time_);
 }
 
 class SiteEngagementServiceTest : public ChromeRenderViewHostTestHarness {