Defer starting of animations until after compositing update

Source/core/animation/AnimationClockTest.cpp

Index: Source/core/animation/AnimationClockTest.cpp
diff --git a/Source/core/animation/AnimationClockTest.cpp b/Source/core/animation/AnimationClockTest.cpp
index 248da7badee6ce73eaeed5f7465cf760c1249c03..f5c75fb40ab6b782daa01c310a2fac307095567a 100644
--- a/Source/core/animation/AnimationClockTest.cpp
+++ b/Source/core/animation/AnimationClockTest.cpp
@@ -48,7 +48,7 @@ protected:
 
     static double mockTimeFunction()
     {
-        return mockTime++;
+        return mockTime;
     }
 
     static double mockTime;
@@ -59,21 +59,29 @@ double AnimationAnimationClockTest::mockTime;
 
 TEST_F(AnimationAnimationClockTest, CurrentTime)
 {
+    // Current time should not advance until minTimeBeforeUnsynchronizedTick has elapsed
     EXPECT_EQ(200, animationClock->currentTime());
+    mockTime = 200 + 0.0025;
     EXPECT_EQ(200, animationClock->currentTime());
-    animationClock->unfreeze();
-    EXPECT_EQ(201, animationClock->currentTime());
-    EXPECT_EQ(201, animationClock->currentTime());
+
+    mockTime = 200 + 0.005;
+    EXPECT_EQ(mockTime, animationClock->currentTime());
 }
 
 TEST_F(AnimationAnimationClockTest, UpdateTime)
 {
     animationClock->updateTime(100);
     EXPECT_EQ(100, animationClock->currentTime());
+    mockTime = 200;
     EXPECT_EQ(100, animationClock->currentTime());
-    animationClock->updateTime(150);
-    EXPECT_EQ(150, animationClock->currentTime());
-    EXPECT_EQ(150, animationClock->currentTime());
+
+    animationClock->unfreeze();
+    EXPECT_EQ(200, animationClock->currentTime());
+
+    animationClock->updateTime(300);
+    EXPECT_EQ(300, animationClock->currentTime());
+    mockTime = 400;
+    EXPECT_EQ(300, animationClock->currentTime());
 }
 
 }