Replaced TestNowSource with SimpleTestTickClock.

base/test/simple_test_tick_clock.h

Index: base/test/simple_test_tick_clock.h
diff --git a/base/test/simple_test_tick_clock.h b/base/test/simple_test_tick_clock.h
index aebdebcbcf54e7016a1629b5405eb40cbf22d801..07bbaf5ddfe9bf6d97060325927daa3c4d4ffc14 100644
--- a/base/test/simple_test_tick_clock.h
+++ b/base/test/simple_test_tick_clock.h
@@ -19,13 +19,21 @@ class SimpleTestTickClock : public TickClock {
  public:
   // Starts off with a clock set to TimeTicks().
   SimpleTestTickClock();
+  SimpleTestTickClock(int64_t initial);

[Paweł Hajdan Jr., 2015/05/26 11:30:25]

Why are these additional ctors needed?

[Ankur Verma, 2015/05/26 12:58:29]

These are convenience ctors really, for usage under cctests. Can be replaced by
callers with Advance().

+  SimpleTestTickClock(TimeTicks initial);
   ~SimpleTestTickClock() override;
 
   TimeTicks NowTicks() override;
+  void Set(TimeTicks time);

[Paweł Hajdan Jr., 2015/05/26 11:30:25]

Why is Set needed?

[Ankur Verma, 2015/05/26 12:58:29]

Again meant for convenient usage under cctests. Can be replaced with Advance(). 

 
   // Advances the clock by |delta|, which must not be negative.
   void Advance(TimeDelta delta);
 
+  // Convenience functions to make the now source easier to use in unit

[Paweł Hajdan Jr., 2015/05/26 11:30:25]

I don't see a reason enough for these convenience methods. Can't callers call
Advance?

[Ankur Verma, 2015/05/26 12:58:29]

I understand SimpleTestTickClock must be as simple as possible. I will remove
these additions and change cctests accordingly.

Thanks for the review.

+  // tests.
+  void AdvanceMicroseconds(int64_t period_in_microseconds);
+  void SetMicroseconds(int64_t time_in_microseconds);
+
  private:
   // Protects |now_ticks_|.
   Lock lock_;