Speculative fix to de-flake AnimationKeyframeEffectV8Test

It appears like calling ResetTimeForTesting is not actually needed for
this test to pass. Since it is causing flake due to the double/TimeTick
round-trips (see bug), just remove it.

Bug: 838676
Change-Id: Ice3e2c88e3afbdf07c52abfb8bffc9d8e0d0c8b1
Reviewed-on: https://chromium-review.googlesource.com/1042380Reviewed-by: Robert Flack <flackr@chromium.org>
Commit-Queue: Stephen McGruer <smcgruer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555902}

third_party/blink/renderer/core/animation/keyframe_effect_test.cc

@@ -31,12 +31,7 @@ class KeyframeEffectTest : public PageTestBase {
   void SetUp() override {
     PageTestBase::SetUp(IntSize());
     element = GetDocument().CreateElementForBinding("foo");
-
-    GetDocument().GetAnimationClock().ResetTimeForTesting(
-        base::TimeTicks() +
-        base::TimeDelta::FromSecondsD(GetDocument().Timeline().ZeroTime()));
     GetDocument().documentElement()->AppendChild(element.Get());
-    EXPECT_EQ(0, GetDocument().Timeline().currentTime());
   }
 
   KeyframeEffectModelBase* CreateEmptyEffectModel() {