Handful of related instant changes:

chrome/browser/instant/promo_counter_unittest.cc

Index: chrome/browser/instant/promo_counter_unittest.cc
diff --git a/chrome/browser/instant/promo_counter_unittest.cc b/chrome/browser/instant/promo_counter_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..43cda777070890523b287b792493101572b98b8b
--- /dev/null
+++ b/chrome/browser/instant/promo_counter_unittest.cc
@@ -0,0 +1,81 @@
+// Copyright (c) 2010 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 "chrome/browser/instant/promo_counter.h"
+#include "chrome/test/testing_profile.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+typedef testing::Test PromoCounterTest;
+
+// Makes sure ShouldShow returns false after the max number of days.
+TEST_F(PromoCounterTest, MaxTimeElapsed) {
+  TestingProfile profile;
+  PromoCounter::RegisterUserPrefs(profile.GetPrefs(), "test");
+
+  base::Time test_time(base::Time::Now());
+  PromoCounter counter(&profile, "test", "test", 2, 2);
+  ASSERT_TRUE(counter.ShouldShow(test_time));
+  ASSERT_TRUE(counter.ShouldShow(test_time + base::TimeDelta::FromHours(2)));
+  ASSERT_FALSE(counter.ShouldShow(test_time + base::TimeDelta::FromDays(4)));
+}
+
+// Makes sure ShouldShow returns false after max number of sessions encountered.
+TEST_F(PromoCounterTest, MaxSessionsLapsed) {
+  TestingProfile profile;
+  PromoCounter::RegisterUserPrefs(profile.GetPrefs(), "test");
+
+  base::Time test_time(base::Time::Now());
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    ASSERT_TRUE(counter.ShouldShow(test_time));
+  }
+
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    ASSERT_TRUE(counter.ShouldShow(test_time));
+  }
+
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    ASSERT_FALSE(counter.ShouldShow(test_time));
+  }
+}
+
+// Makes sure invoking Hide make ShouldShow return false.
+TEST_F(PromoCounterTest, Hide) {
+  TestingProfile profile;
+  PromoCounter::RegisterUserPrefs(profile.GetPrefs(), "test");
+
+  base::Time test_time(base::Time::Now());
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    counter.Hide();
+    ASSERT_FALSE(counter.ShouldShow(test_time));
+  }
+
+  // Recreate to make sure pref was correctly written.
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    ASSERT_FALSE(counter.ShouldShow(test_time));
+  }
+}
+
+// Same as Hide, but invokes ShouldShow first.
+TEST_F(PromoCounterTest, Hide2) {
+  TestingProfile profile;
+  PromoCounter::RegisterUserPrefs(profile.GetPrefs(), "test");
+
+  base::Time test_time(base::Time::Now());
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    ASSERT_TRUE(counter.ShouldShow(test_time));
+    counter.Hide();
+    ASSERT_FALSE(counter.ShouldShow(test_time));
+  }
+
+  {
+    PromoCounter counter(&profile, "test", "test", 2, 2);
+    ASSERT_FALSE(counter.ShouldShow(test_time));
+  }
+}