Optimize style recalc when adding @keyframes.

third_party/WebKit/Source/core/animation/AnimationTimeline.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/animation/AnimationTimeline.h"
 
 #include "core/animation/AnimationClock.h"
 #include "core/animation/ElementAnimations.h"
 #include "core/dom/Document.h"
+#include "core/dom/StyleChangeReason.h"
 #include "core/frame/FrameView.h"
 #include "core/loader/DocumentLoader.h"
 #include "core/page/Page.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/TraceEvent.h"
 #include "platform/animation/CompositorAnimationTimeline.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebCompositorSupport.h"
 #include "wtf/PtrUtil.h"
 #include <algorithm>
@@ skipping 18 matching lines @@
 {
     return new AnimationTimeline(document, timing);
 }
 
 AnimationTimeline::AnimationTimeline(Document* document, PlatformTiming* timing)
     : m_document(document)
     , m_zeroTime(0) // 0 is used by unit tests which cannot initialize from the loader
     , m_zeroTimeInitialized(false)
     , m_outdatedAnimationCount(0)
     , m_playbackRate(1)
     , m_lastCurrentTimeInternal(0)

[alancutter (OOO until 2018), 2016/06/29 03:41:32]

We should initialise m_hasUnresolvedKeyframesRule here.

 {
     ThreadState::current()->registerPreFinalizer(this);
     if (!timing)
         m_timing = new AnimationTimelineTiming(this);
     else
         m_timing = timing;
 
     if (Platform::current()->isThreadedAnimationEnabled())
         m_compositorTimeline = CompositorAnimationTimeline::create();
 
@@ skipping 255 matching lines @@
     for (const auto& animation : m_animations) {
         animation->setCompositorPending(sourceChanged);
     }
 }
 
 double AnimationTimeline::playbackRate() const
 {
     return m_playbackRate;
 }
 
+void AnimationTimeline::keyframesRulesAdded()
+{
+    if (m_hasUnresolvedKeyframesRule) {
+        m_hasUnresolvedKeyframesRule = false;
+        if (m_document)
+            m_document->setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::Animation));
+        return;
+    }
+
+    for (const auto& animation : m_animations) {
+        const AnimationEffect* effect = animation->effect();
+        if (!effect)
+            continue;
+        if (!effect->isKeyframeEffect())
+            continue;
+        toKeyframeEffect(effect)->target()->setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::Animation));
+    }
+}
+
 DEFINE_TRACE(AnimationTimeline)
 {
     visitor->trace(m_document);
     visitor->trace(m_timing);
     visitor->trace(m_animationsNeedingUpdate);
     visitor->trace(m_animations);
 }
 
 } // namespace blink