Use-count when SMIL animation renders a frame

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

Index: third_party/WebKit/Source/core/svg/animation/SMILTimeContainer.cpp
diff --git a/third_party/WebKit/Source/core/svg/animation/SMILTimeContainer.cpp b/third_party/WebKit/Source/core/svg/animation/SMILTimeContainer.cpp
index 2d3d2d3c6140763cd1bbebf5a2f1ebfc18ec43eb..55cf1c8b2e857a67c7d8ce0373ab5373d6d7b1f9 100644
--- a/third_party/WebKit/Source/core/svg/animation/SMILTimeContainer.cpp
+++ b/third_party/WebKit/Source/core/svg/animation/SMILTimeContainer.cpp
@@ -30,6 +30,7 @@
 #include "core/dom/ElementTraversal.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/Settings.h"
+#include "core/frame/UseCounter.h"
 #include "core/svg/SVGSVGElement.h"
 #include "core/svg/animation/SVGSMILElement.h"
 #include <algorithm>
@@ -47,6 +48,7 @@ SMILTimeContainer::SMILTimeContainer(SVGSVGElement& owner)
     , m_presetStartTime(0)
     , m_frameSchedulingState(Idle)
     , m_documentOrderIndexesDirty(false)
+    , m_hasUpdatedAnimation(false)
     , m_wakeupTimer(this, &SMILTimeContainer::wakeupTimerFired)
     , m_animationPolicyOnceTimer(this, &SMILTimeContainer::animationPolicyTimerFired)
     , m_ownerSVGElement(&owner)
@@ -512,6 +514,11 @@ SMILTime SMILTimeContainer::updateAnimations(SMILTime elapsed, bool seekToTime)
         return earliestFireTime;
     }
 
+    if (!m_hasUpdatedAnimation) {
+        m_hasUpdatedAnimation = true;
+        UseCounter::count(&document(), UseCounter::SVGSMILAnimationAppliedEffect);

[fs, 2016/07/21 10:17:33]

You could ditch the m_hasUpdatedAnimation - once the "counter" (flag) is set, it
is set. I don't think the additional overhead is something worth caring about
(unless prompted.)

[suzyh_UTC10 (ex-contributor), 2016/07/25 03:16:00]

Done.

+    }
+
     // Apply results to target elements.
     for (unsigned i = 0; i < animationsToApplySize; ++i)
         animationsToApply[i]->applyResultsToTarget();