[ScopedTaskEnvironment] Remove unused MOCK_TIME_AND_NOW

Made equivalent to MOCK_TIME in crrev.com/683487
Usage migrated in crrev.com/683751

R=kylechar@chromium.org

Bug: 905412
Change-Id: Icae6b24300a4e9a11e486244178cd34f46a73a2f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733931Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Gabriel Charette <gab@chromium.org>
Auto-Submit: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#684306}

base/test/scoped_task_environment.cc

@@ -357,7 +357,7 @@ ScopedTaskEnvironment::ScopedTaskEnvironment(
           time_source != TimeSource::SYSTEM_TIME
               ? MockTimeDomain::CreateAndRegister(sequence_manager_.get())
               : nullptr),
-      time_overrides_(time_source == TimeSource::MOCK_TIME_AND_NOW
+      time_overrides_(time_source == TimeSource::MOCK_TIME
                           ? std::make_unique<subtle::ScopedTimeClockOverrides>(
                                 &MockTimeDomain::GetTime,
                                 &MockTimeDomain::GetTimeTicks,

base/test/scoped_task_environment.h

@@ -104,10 +104,6 @@ class ScopedTaskEnvironment {
     //     runners.
     MOCK_TIME,
 
-    // TODO(gab): MOCK_TIME is now equivalent to MOCK_TIME_AND_NOW. Mass migrate
-    // users of MOCK_TIME_AND_NOW to MOCK_TIME.
-    MOCK_TIME_AND_NOW = MOCK_TIME,
-
     // TODO(gab): Consider making MOCK_TIME the default mode.
     DEFAULT = SYSTEM_TIME
   };
@@ -232,10 +228,11 @@ class ScopedTaskEnvironment {
   // process. See time.h.
   const Clock* GetMockClock() const;
 
-  // Only valid for instances using TimeSource::MOCK_TIME. Returns the
-  // current virtual tick time (based on a realistic Now(), sampled when this
+  // Only valid for instances using TimeSource::MOCK_TIME. Returns the current
+  // virtual tick time (based on a realistic Now(), sampled when this
   // ScopedTaskEnvironment was created, and manually advanced from that point
-  // on).
+  // on). This is always equivalent to base::TimeTicks::Now() under
+  // TimeSource::MOCK_TIME.
   base::TimeTicks NowTicks() const;
 
   // Only valid for instances using TimeSource::MOCK_TIME. Returns the

base/test/scoped_task_environment_unittest.cc

@@ -449,7 +449,7 @@ TEST_F(ScopedTaskEnvironmentTest, FastForwardAdvanceMockClock) {
 TEST_F(ScopedTaskEnvironmentTest, FastForwardAdvanceTime) {
   constexpr base::TimeDelta kDelay = TimeDelta::FromSeconds(42);
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
 
   const Time start_time = base::Time::Now();
   scoped_task_environment.FastForwardBy(kDelay);
@@ -459,7 +459,7 @@ TEST_F(ScopedTaskEnvironmentTest, FastForwardAdvanceTime) {
 TEST_F(ScopedTaskEnvironmentTest, FastForwardAdvanceTimeTicks) {
   constexpr base::TimeDelta kDelay = TimeDelta::FromSeconds(42);
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
 
   const TimeTicks start_time = base::TimeTicks::Now();
   scoped_task_environment.FastForwardBy(kDelay);
@@ -471,7 +471,7 @@ TEST_F(ScopedTaskEnvironmentTest, FastForwardAdvanceTimeTicks) {
 // of time when out of tasks.
 TEST_F(ScopedTaskEnvironmentTest, FastForwardOnlyAdvancesWhenIdle) {
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
 
   const TimeTicks start_time = base::TimeTicks::Now();
 
@@ -573,7 +573,7 @@ TEST_F(ScopedTaskEnvironmentTest, NestedRunInFastForwardBy) {
 TEST_F(ScopedTaskEnvironmentTest,
        CrossThreadImmediateTaskPostingDoesntAffectMockTime) {
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
 
   int count = 0;
 
@@ -1104,16 +1104,19 @@ TEST_F(ScopedTaskEnvironmentTest,
             scoped_task_environment.NextMainThreadPendingTaskDelay());
 }
 
-TEST_F(ScopedTaskEnvironmentTest, TimeSourceMockTimeAndNow) {
+TEST_F(ScopedTaskEnvironmentTest, TimeSourceMockTimeAlsoMocksNow) {
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
 
-  const TimeTicks start_time = scoped_task_environment.NowTicks();
-  EXPECT_EQ(TimeTicks::Now(), start_time);
+  const TimeTicks start_ticks = scoped_task_environment.NowTicks();
+  EXPECT_EQ(TimeTicks::Now(), start_ticks);
+
+  const Time start_time = Time::Now();
 
   constexpr TimeDelta kDelay = TimeDelta::FromSeconds(10);
   scoped_task_environment.FastForwardBy(kDelay);
-  EXPECT_EQ(TimeTicks::Now(), start_time + kDelay);
+  EXPECT_EQ(TimeTicks::Now(), start_ticks + kDelay);
+  EXPECT_EQ(Time::Now(), start_time + kDelay);
 }
 
 }  // namespace test

base/timer/lap_timer_unittest.cc

@@ -27,7 +27,7 @@ constexpr int kTimeCheckInterval = 10;
 
 TEST(LapTimer, UsageExample) {
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
 
   LapTimer timer(kWarmupRuns, kTimeLimit, kTimeCheckInterval);
 
@@ -53,7 +53,7 @@ TEST(LapTimer, UsageExample) {
 // iOS simulator does not support using ThreadTicks.
 TEST(LapTimer, ThreadTicksUsageExample) {
   ScopedTaskEnvironment scoped_task_environment(
-      ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW);
+      ScopedTaskEnvironment::TimeSource::MOCK_TIME);
   LapTimer timer(kWarmupRuns, kTimeLimit, kTimeCheckInterval,
                  LapTimer::TimerMethod::kUseThreadTicks);
 

base/timer/timer.h

@@ -114,12 +114,10 @@ class BASE_EXPORT TimerBase {
   // this Timer is running. This method can only be called while this Timer
   // isn't running. This is an alternative (old) approach to mock time in tests.
   // The modern and preferred approach is to use
-  // ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW (more reliable than
-  // TimeSource::MOCK_TIME if the Timer is ever restarted and needs to compare
-  // with the current TimeTicks::Now()). To avoid racy usage of Timer,
+  // ScopedTaskEnvironment::TimeSource::MOCK_TIME. To avoid racy usage of Timer,
   // |task_runner| must run tasks on the same sequence which this Timer is bound
   // to (started from). TODO(gab): Migrate all callers to
-  // ScopedTaskEnvironment::TimeSource::MOCK_TIME_AND_NOW.
+  // ScopedTaskEnvironment::TimeSource::MOCK_TIME.
   virtual void SetTaskRunner(scoped_refptr<SequencedTaskRunner> task_runner);
 
   // Call this method to stop and cancel the timer.  It is a no-op if the timer