FirstMeaningfulPaint UMA

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 47 matching lines @@
 void PaintTiming::markFirstImagePaint()
 {
     if (m_firstImagePaint != 0.0)
         return;
     m_firstImagePaint = monotonicallyIncreasingTime();
     setFirstContentfulPaint(m_firstImagePaint);
     TRACE_EVENT_MARK_WITH_TIMESTAMP1("blink.user_timing", "firstImagePaint", m_firstImagePaint, "frame", frame());
     notifyPaintTimingChanged();
 }
 
+void PaintTiming::setFirstMeaningfulPaint(double stamp)
+{
+    DCHECK_EQ(m_firstMeaningfulPaint, 0.0);
+    m_firstMeaningfulPaint = stamp;
+    notifyPaintTimingChanged();
+}
+
 DEFINE_TRACE(PaintTiming)
 {
     visitor->trace(m_document);
+    visitor->trace(m_fmpDetector);
     Supplement<Document>::trace(visitor);
 }
 
 PaintTiming::PaintTiming(Document& document)
     : m_document(document)
+    , m_fmpDetector(new FirstMeaningfulPaintDetector(this))
 {
 }
 
 LocalFrame* PaintTiming::frame() const
 {
     return m_document ? m_document->frame() : nullptr;
 }
 
 void PaintTiming::notifyPaintTimingChanged()
 {
@@ skipping 12 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