Add RAIL tracing category to Chrome tracing.

third_party/WebKit/Source/core/page/PageAnimator.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/page/PageAnimator.h"
 
 #include "core/animation/DocumentAnimations.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/page/ChromeClient.h"
@@ skipping 27 matching lines @@
     clock().updateTime(monotonicAnimationStartTime);
 
     HeapVector<Member<Document>, 32> documents;
     for (Frame* frame = m_page->mainFrame(); frame; frame = frame->tree().traverseNext()) {
         if (frame->isLocalFrame())
             documents.append(toLocalFrame(frame)->document());
     }
 
     for (auto& document : documents) {
         ScopedFrameBlamer frameBlamer(document->frame());
-        TRACE_EVENT0("blink", "PageAnimator::serviceScriptedAnimations");
+        TRACE_EVENT0("blink,rail", "PageAnimator::serviceScriptedAnimations");
         DocumentAnimations::updateAnimationTimingForAnimationFrame(*document);
         if (document->view()) {
             if (document->view()->shouldThrottleRendering())
                 continue;
             // Disallow throttling in case any script needs to do a synchronous
             // lifecycle update in other frames which are throttled.
             DocumentLifecycle::DisallowThrottlingScope noThrottlingScope(document->lifecycle());
             if (ScrollableArea* scrollableArea = document->view()->getScrollableArea())
                 scrollableArea->serviceScrollAnimations(monotonicAnimationStartTime);
 
@@ skipping 21 matching lines @@
 }
 
 void PageAnimator::updateAllLifecyclePhases(LocalFrame& rootFrame)
 {
     FrameView* view = rootFrame.view();
     AutoReset<bool> servicing(&m_updatingLayoutAndStyleForPainting, true);
     view->updateAllLifecyclePhases();
 }
 
 } // namespace blink