Web Animations: Expose timeline currentTime in IDL

Source/core/animation/DocumentTimelineTest.cpp

Index: Source/core/animation/DocumentTimelineTest.cpp
diff --git a/Source/core/animation/DocumentTimelineTest.cpp b/Source/core/animation/DocumentTimelineTest.cpp
index 8be0696c8a4a9a4effeab5ccc3dd2b62477a5a05..b2e64ece84c40da6af2fd86081a6a17c4cc8aaaa 100644
--- a/Source/core/animation/DocumentTimelineTest.cpp
+++ b/Source/core/animation/DocumentTimelineTest.cpp
@@ -169,9 +169,12 @@ TEST_F(AnimationDocumentTimelineTest, EmptyForwardsKeyframeAnimation)
 TEST_F(AnimationDocumentTimelineTest, ZeroTime)
 {
     timeline = DocumentTimeline::create(document.get());
+    bool isNullTime;
 
     document->animationClock().updateTime(100);
     EXPECT_TRUE(isNull(timeline->currentTime()));
+    EXPECT_TRUE(isNull(timeline->currentTime(isNullTime)));
+    EXPECT_TRUE(isNullTime);
 
     document->animationClock().updateTime(200);
     EXPECT_TRUE(isNull(timeline->currentTime()));
@@ -179,6 +182,8 @@ TEST_F(AnimationDocumentTimelineTest, ZeroTime)
     timeline->setZeroTime(300);
     document->animationClock().updateTime(300);
     EXPECT_EQ(0, timeline->currentTime());
+    EXPECT_EQ(0, timeline->currentTime(isNullTime));
+    EXPECT_FALSE(isNullTime);
 
     document->animationClock().updateTime(400);
     EXPECT_EQ(100, timeline->currentTime());