first-paint and first-contentful paint

third_party/WebKit/Source/core/timing/PerformanceBase.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2012 Intel 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 139 matching lines @@
       }
       break;
     case PerformanceEntry::Mark:
       if (m_userTiming)
         entries.appendVector(m_userTiming->getMarks());
       break;
     case PerformanceEntry::Measure:
       if (m_userTiming)
         entries.appendVector(m_userTiming->getMeasures());
       break;
-    // Unsupported for LongTask, TaskAttribution.
+    // Unsupported for Paint, LongTask, TaskAttribution.
     // Per the spec, these entries can only be accessed via
     // Performance Observer. No separate buffer is maintained.
+    case PerformanceEntry::Paint:
+      break;
     case PerformanceEntry::LongTask:
       break;
     case PerformanceEntry::TaskAttribution:
       break;
     case PerformanceEntry::Invalid:
       break;
   }
 
   std::sort(entries.begin(), entries.end(),
             PerformanceEntry::startTimeCompareLessThan);
@@ skipping 220 matching lines @@
       documentTiming ? documentTiming->domComplete() : 0, type,
       documentLoadTiming.redirectStart(), documentLoadTiming.redirectEnd(),
       documentLoadTiming.fetchStart(), documentLoadTiming.responseEnd(),
       allowRedirectDetails,
       documentLoadTiming.hasSameOriginAsPreviousDocument(), resourceLoadTiming,
       lastRedirectEndTime, finishTime, transferSize, encodedBodyLength,
       decodedBodyLength, didReuseConnection);
   notifyObserversOfEntry(*m_navigationTiming);
 }
 
+void PerformanceBase::addFirstPaintTiming(double startTime) {
+  addPaintTiming(PerformancePaintTiming::PaintType::FirstPaint, startTime);
+}
+
+void PerformanceBase::addFirstContentfulPaintTiming(double startTime) {
+  addPaintTiming(PerformancePaintTiming::PaintType::FirstContentfulPaint,
+                 startTime);
+}
+
+void PerformanceBase::addPaintTiming(PerformancePaintTiming::PaintType type,
+                                     double startTime) {
+  if (!RuntimeEnabledFeatures::performancePaintTimingEnabled())
+    return;
+  PerformanceEntry* entry = new PerformancePaintTiming(
+      type, monotonicTimeToDOMHighResTimeStamp(startTime));
+  notifyObserversOfEntry(*entry);
+}
+
 void PerformanceBase::addResourceTimingBuffer(PerformanceEntry& entry) {
   m_resourceTimingBuffer.push_back(&entry);
 
   if (isResourceTimingBufferFull())
     dispatchEvent(Event::create(EventTypeNames::resourcetimingbufferfull));
 }
 
 bool PerformanceBase::isResourceTimingBufferFull() {
   return m_resourceTimingBuffer.size() >= m_resourceTimingBufferSize;
 }
@@ skipping 137 matching lines @@
 }
 
 DOMHighResTimeStamp PerformanceBase::monotonicTimeToDOMHighResTimeStamp(
     double timeOrigin,
     double monotonicTime) {
   // Avoid exposing raw platform timestamps.
   if (!monotonicTime || !timeOrigin)
     return 0.0;
 
   double timeInSeconds = monotonicTime - timeOrigin;
-  DCHECK_GE(timeInSeconds, 0);
+  if (timeInSeconds < 0)
+    return 0.0;
   return convertSecondsToDOMHighResTimeStamp(
       clampTimeResolution(timeInSeconds));
 }
 
 DOMHighResTimeStamp PerformanceBase::monotonicTimeToDOMHighResTimeStamp(
     double monotonicTime) const {
   return monotonicTimeToDOMHighResTimeStamp(m_timeOrigin, monotonicTime);
 }
 
 DOMHighResTimeStamp PerformanceBase::now() const {
   return monotonicTimeToDOMHighResTimeStamp(monotonicallyIncreasingTime());
 }
 
 DEFINE_TRACE(PerformanceBase) {
   visitor->trace(m_frameTimingBuffer);
   visitor->trace(m_resourceTimingBuffer);
   visitor->trace(m_navigationTiming);
   visitor->trace(m_userTiming);
   visitor->trace(m_observers);
   visitor->trace(m_activeObservers);
   visitor->trace(m_suspendedObservers);
   EventTargetWithInlineData::trace(visitor);
 }
 
 }  // namespace blink