Revert "Speculative revert by sheriff"

media/base/wall_clock_time_source_unittest.cc

Index: media/base/wall_clock_time_source_unittest.cc
diff --git a/media/base/wall_clock_time_source_unittest.cc b/media/base/wall_clock_time_source_unittest.cc
index 08a424d42a406de06e6900d77f2ca8ed15f1c863..fe8e04c1e82ad4460fa9c625106f13b39cb663bf 100644
--- a/media/base/wall_clock_time_source_unittest.cc
+++ b/media/base/wall_clock_time_source_unittest.cc
@@ -13,6 +13,7 @@ class WallClockTimeSourceTest : public testing::Test {
   WallClockTimeSourceTest() : tick_clock_(new base::SimpleTestTickClock()) {
     time_source_.SetTickClockForTesting(
         scoped_ptr<base::TickClock>(tick_clock_));
+    AdvanceTimeInSeconds(1);
   }
   ~WallClockTimeSourceTest() override {}
 
@@ -28,9 +29,18 @@ class WallClockTimeSourceTest : public testing::Test {
     return time_source_.SetMediaTime(base::TimeDelta::FromSeconds(seconds));
   }
 
-  WallClockTimeSource time_source_;
+  bool IsWallClockNowForMediaTimeInSeconds(int seconds) {
+    return tick_clock_->NowTicks() ==
+           time_source_.GetWallClockTime(base::TimeDelta::FromSeconds(seconds));
+  }
 
- private:
+  bool IsWallClockNullForMediaTimeInSeconds(int seconds) {
+    return time_source_.GetWallClockTime(base::TimeDelta::FromSeconds(seconds))
+        .is_null();
+  }
+
+ protected:
+  WallClockTimeSource time_source_;
   base::SimpleTestTickClock* tick_clock_;  // Owned by |time_source_|.
 
   DISALLOW_COPY_AND_ASSIGN(WallClockTimeSourceTest);
@@ -38,26 +48,33 @@ class WallClockTimeSourceTest : public testing::Test {
 
 TEST_F(WallClockTimeSourceTest, InitialTimeIsZero) {
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNullForMediaTimeInSeconds(0));
 }
 
 TEST_F(WallClockTimeSourceTest, InitialTimeIsNotTicking) {
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNullForMediaTimeInSeconds(0));
   AdvanceTimeInSeconds(100);
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNullForMediaTimeInSeconds(0));
 }
 
 TEST_F(WallClockTimeSourceTest, InitialPlaybackRateIsOne) {
   time_source_.StartTicking();
 
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(0));
   AdvanceTimeInSeconds(100);
   EXPECT_EQ(100, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(100));
 }
 
 TEST_F(WallClockTimeSourceTest, SetMediaTime) {
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNullForMediaTimeInSeconds(0));
   SetMediaTimeInSeconds(10);
   EXPECT_EQ(10, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNullForMediaTimeInSeconds(10));
 }
 
 TEST_F(WallClockTimeSourceTest, SetPlaybackRate) {
@@ -65,26 +82,33 @@ TEST_F(WallClockTimeSourceTest, SetPlaybackRate) {
 
   time_source_.SetPlaybackRate(0.5);
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(0));
   AdvanceTimeInSeconds(10);
   EXPECT_EQ(5, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(5));
 
   time_source_.SetPlaybackRate(2);
   EXPECT_EQ(5, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(5));
   AdvanceTimeInSeconds(10);
   EXPECT_EQ(25, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(25));
 }
 
 TEST_F(WallClockTimeSourceTest, StopTicking) {
   time_source_.StartTicking();
 
   EXPECT_EQ(0, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(0));
   AdvanceTimeInSeconds(10);
   EXPECT_EQ(10, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNowForMediaTimeInSeconds(10));
 
   time_source_.StopTicking();
 
   AdvanceTimeInSeconds(10);
   EXPECT_EQ(10, CurrentMediaTimeInSeconds());
+  EXPECT_TRUE(IsWallClockNullForMediaTimeInSeconds(10));
 }
 
 }  // namespace media