Fix PrePaint UMA when SlimmingPaintInvalidation is disabled

third_party/WebKit/Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 3010 matching lines @@
     if (scroller) {
       DCHECK(scroller->scrollAnchor());
       scroller->scrollAnchor()->adjust();
     }
   }
   m_anchoringAdjustmentQueue.clear();
 }
 
 void FrameView::prePaint() {
   TRACE_EVENT0("blink", "FrameView::prePaint");
-  SCOPED_BLINK_UMA_HISTOGRAM_TIMER("Blink.PrePaint.UpdateTime");
 
   if (!m_paintController)
     m_paintController = PaintController::create();
 
   if (!m_geometryMapper)
     m_geometryMapper.reset(new GeometryMapper());
   // TODO(chrishtr): the cache only needs to be invalidated if one or more of
   // the property tree nodes changed.
   m_geometryMapper->clearCache();
 
   forAllNonThrottledFrameViews([](FrameView& frameView) {
     frameView.lifecycle().advanceTo(DocumentLifecycle::InPrePaint);
     if (frameView.canThrottleRendering()) {
       // This frame can be throttled but not throttled, meaning we are not in an
       // AllowThrottlingScope. Now this frame may contain dirty paint flags, and
       // we need to propagate the flags into the ancestor chain so that
       // PrePaintTreeWalk can reach this frame.
       frameView.setNeedsPaintPropertyUpdate();
     }
   });
 
-  if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled())
+  if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled()) {
+    SCOPED_BLINK_UMA_HISTOGRAM_TIMER("Blink.PrePaint.UpdateTime");
     PrePaintTreeWalk(*m_geometryMapper).walk(*this);
+  }
 
   forAllNonThrottledFrameViews([](FrameView& frameView) {
     frameView.lifecycle().advanceTo(DocumentLifecycle::PrePaintClean);
   });
 }
 
 void FrameView::notifyPaint(const PaintController& paintController) const {
   DCHECK(m_frame->document());
   PaintTiming::from(*m_frame->document())
       .notifyPaint(paintController.firstPainted(),
@@ skipping 2030 matching lines @@
     std::unique_ptr<CompositorAnimationTimeline> timeline) {
   m_animationTimeline = std::move(timeline);
 }
 
 void FrameView::setAnimationHost(
     std::unique_ptr<CompositorAnimationHost> host) {
   m_animationHost = std::move(host);
 }
 
 }  // namespace blink