Refactor SMILTimeContainer can-schedule-frame predicate

third_party/WebKit/Source/core/svg/animation/SMILTimeContainer.cpp

 /*
  * Copyright (C) 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 165 matching lines @@
         return;
 
     // Sample the document timeline to get a time reference for the "presentation time".
     synchronizeToDocumentTimeline();
     m_started = true;
 
     // If the "presentation time" is non-zero, the timeline was modified via
     // setElapsed() before the document began.
     // In this case pass on 'seekToTime=true' to updateAnimations() to issue a seek.
     SMILTime earliestFireTime = updateAnimations(SMILTime(m_presentationTime), m_presentationTime ? true : false);
-
-    if (isPaused()) {
-        // If updateAnimations() caused new syncbase instances to be generated,
-        // we don't want to cancel those. Excepting that, no frame should've
-        // been scheduled at this point.
-        DCHECK(m_frameSchedulingState == Idle || m_frameSchedulingState == SynchronizeAnimations);
-        return;
-    }
-    // If synchronizations are pending, those will in turn schedule additional
-    // frames.
-    if (hasPendingSynchronization())
-        return;
-    DCHECK(isTimelineRunning());
-    if (!earliestFireTime.isFinite())
+    if (!canScheduleFrame(earliestFireTime))
         return;
     // If the timeline is running, and there are pending animation updates,
     // always perform the first update after the timeline was started using
     // the wake-up mechanism.
     SMILTime delay = earliestFireTime - m_presentationTime;
     scheduleWakeUp(std::max(initialFrameDelay, delay.value()), SynchronizeAnimations);
 }
 
 void SMILTimeContainer::pause()
 {
@@ skipping 200 matching lines @@
 
 void SMILTimeContainer::serviceAnimations()
 {
     if (m_frameSchedulingState != AnimationFrame)
         return;
 
     m_frameSchedulingState = Idle;
     updateAnimationsAndScheduleFrameIfNeeded(elapsed());
 }
 
+bool SMILTimeContainer::canScheduleFrame(SMILTime earliestFireTime) const
+{
+    // If there's synchronization pending (most likely due to syncbases), then
+    // let that complete first before attempting to schedule a frame.
+    if (hasPendingSynchronization())
+        return false;
+    if (!isTimelineRunning())
+        return false;
+    return earliestFireTime.isFinite();
+}
+
 void SMILTimeContainer::updateAnimationsAndScheduleFrameIfNeeded(SMILTime elapsed, bool seekToTime)
 {
     if (!document().isActive())
         return;
 
     SMILTime earliestFireTime = updateAnimations(elapsed, seekToTime);
-    // If updateAnimations() ended up triggering a synchronization (most likely
-    // via syncbases), then give that priority.
-    if (hasPendingSynchronization())
+    if (!canScheduleFrame(earliestFireTime))
         return;
-
-    if (!isTimelineRunning())
-        return;
-
-    if (!earliestFireTime.isFinite())
-        return;
-
     SMILTime delay = earliestFireTime - elapsed;
     scheduleAnimationFrame(delay.value());
 }
 
 SMILTime SMILTimeContainer::updateAnimations(SMILTime elapsed, bool seekToTime)
 {
     ASSERT(document().isActive());
     SMILTime earliestFireTime = SMILTime::unresolved();
 
 #if ENABLE(ASSERT)
@@ skipping 98 matching lines @@
     setElapsed(elapsed().value() + initialFrameDelay);
 }
 
 DEFINE_TRACE(SMILTimeContainer)
 {
     visitor->trace(m_scheduledAnimations);
     visitor->trace(m_ownerSVGElement);
 }
 
 } // namespace blink