Add missing traces for Supplement<> classes

third_party/WebKit/Source/core/paint/PaintTiming.cpp

 // Copyright 2015 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/paint/PaintTiming.h"
 
 #include "core/dom/Document.h"
 #include "core/loader/DocumentLoader.h"
 #include "platform/TraceEvent.h"
 
@@ skipping 50 matching lines @@
         return;
     m_firstImagePaint = monotonicallyIncreasingTime();
     setFirstContentfulPaint(m_firstImagePaint);
     TRACE_EVENT_MARK_WITH_TIMESTAMP1("blink.user_timing", "firstImagePaint", m_firstImagePaint, "frame", frame());
     notifyPaintTimingChanged();
 }
 
 DEFINE_TRACE(PaintTiming)
 {
     visitor->trace(m_document);
+    Supplement<Document>::trace(visitor);
 }
 
 PaintTiming::PaintTiming(Document& document)
     : m_document(document)
 {
 }
 
 LocalFrame* PaintTiming::frame() const
 {
     return m_document ? m_document->frame() : nullptr;
@@ skipping 16 matching lines @@
 void PaintTiming::setFirstContentfulPaint(double stamp)
 {
     if (m_firstContentfulPaint != 0.0)
         return;
     setFirstPaint(stamp);
     m_firstContentfulPaint = stamp;
     TRACE_EVENT_INSTANT1("blink.user_timing", "firstContentfulPaint", TRACE_EVENT_SCOPE_PROCESS, "frame", frame());
 }
 
 } // namespace blink