Implement requestAnimationFrame

Cherry-pick from webkit-org branch on Code Aurora Forum:

requestAnimationFrame doesn't throttle on Mac
https://www.codeaurora.org/gitweb/quic/la/?p=platform/external/webkit.git;a=commit;h=d9dca741b4762c433ae18f7a1bc59a3a81861fc8

Timestamp parameter to requestAnimationFrame is busted in USE(REQUEST_ANIMATION_FRAME_TIMER) path
https://www.codeaurora.org/gitweb/quic/la/?p=platform/external/webkit.git;a=commit;h=f0909a46fa167c84062c63caffef340a6054bc1e

Rename webkitCancelRequestAnimationFrame to webkitCancelAnimationFrame to match spec change
https://www.codeaurora.org/gitweb/quic/la/?p=platform/external/webkit.git;a=commit;h=cd5d11d662d638b3e4dfda33f23cda907f007f12

Remove partially implemented per-Element visibility checks from requestAnimationFrame logic
https://www.codeaurora.org/gitweb/quic/la/?p=platform/external/webkit.git;a=commit;h=9fb90af3cebd0e595990cded0941d230cf77dcc1

(cherry picked from commit 47ff59a279eab9ae5dd1fd17ce7057431750a0b5)

Change-Id: I7e77200006bb0c4cd4b4209082296c425bd207c1

1 files changed, 37 insertions, 0 deletions

diff --git a/LayoutTests/fast/animation/script-tests/request-animation-frame-timestamps-advance.js b/LayoutTests/fast/animation/script-tests/request-animation-frame-timestamps-advance.js
new file mode 100644
index 0000000..52d9b90
--- /dev/null
+++ b/LayoutTests/fast/animation/script-tests/request-animation-frame-timestamps-advance.js
@@ -0,0 +1,37 @@
+description("Tests the timestamps provided to requestAnimationFrame callbacks advance");
+
+function busyWait(millis) {
+    var start = Date.now();
+    while (Date.now()-start < millis) {}
+}
+
+var firstTimestamp = undefined;
+var secondTimestamp = undefined;
+
+window.webkitRequestAnimationFrame(function(timestamp) {
+    firstTimestamp = timestamp;
+    shouldBeDefined("firstTimestamp");
+    window.webkitRequestAnimationFrame(function(timestamp) {
+        secondTimestamp = timestamp;
+        shouldBeDefined("secondTimestamp");
+        shouldBeTrue("secondTimestamp > firstTimestamp");
+        isSuccessfullyParsed();
+        if (window.layoutTestController)
+            layoutTestController.notifyDone();
+    });
+    busyWait(10);
+    if (window.layoutTestController)
+        layoutTestController.display();
+});
+
+
+if (window.layoutTestController)
+    window.setTimeout(function() {
+        layoutTestController.display();
+    });
+
+
+if (window.layoutTestController)
+    layoutTestController.waitUntilDone();
+
+var successfullyParsed = true;