DevTools: do not report paint metrics under blink.user_timing category.

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/frame/FrameView.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 49 matching lines @@
   setFirstContentfulPaint(monotonicallyIncreasingTime());
   notifyPaintTimingChanged();
 }
 
 void PaintTiming::markFirstTextPaint() {
   if (m_firstTextPaint != 0.0)
     return;
   m_firstTextPaint = monotonicallyIncreasingTime();
   setFirstContentfulPaint(m_firstTextPaint);
   TRACE_EVENT_MARK_WITH_TIMESTAMP1(
-      "blink.user_timing,rail", "firstTextPaint",
+      "rail,devtools.timeline", "firstTextPaint",
       TraceEvent::toTraceTimestamp(m_firstTextPaint), "frame", frame());
   notifyPaintTimingChanged();
 }
 
 void PaintTiming::markFirstImagePaint() {
   if (m_firstImagePaint != 0.0)
     return;
   m_firstImagePaint = monotonicallyIncreasingTime();
   setFirstContentfulPaint(m_firstImagePaint);
   TRACE_EVENT_MARK_WITH_TIMESTAMP1(
-      "blink.user_timing,rail", "firstImagePaint",
+      "rail,devtools.timeline", "firstImagePaint",
       TraceEvent::toTraceTimestamp(m_firstImagePaint), "frame", frame());
   notifyPaintTimingChanged();
 }
 
 void PaintTiming::setFirstMeaningfulPaintCandidate(double timestamp) {
   if (m_firstMeaningfulPaintCandidate)
     return;
   m_firstMeaningfulPaintCandidate = timestamp;
   if (frame() && frame()->view() && !frame()->view()->parent()) {
     frame()->frameScheduler()->onFirstMeaningfulPaint();
   }
 }
 
 void PaintTiming::setFirstMeaningfulPaint(double stamp) {
   DCHECK_EQ(m_firstMeaningfulPaint, 0.0);
   m_firstMeaningfulPaint = stamp;
   TRACE_EVENT_MARK_WITH_TIMESTAMP1(
-      "blink.user_timing", "firstMeaningfulPaint",
+      "rail,devtools.timeline", "firstMeaningfulPaint",
       TraceEvent::toTraceTimestamp(m_firstMeaningfulPaint), "frame", frame());
   notifyPaintTimingChanged();
 }
 
 void PaintTiming::notifyPaint(bool isFirstPaint,
                               bool textPainted,
                               bool imagePainted) {
   if (isFirstPaint)
     markFirstPaint();
   if (textPainted)
@@ skipping 22 matching lines @@
 }
 
 void PaintTiming::setFirstPaint(double stamp) {
   if (m_firstPaint != 0.0)
     return;
   m_firstPaint = stamp;
   Performance* performance = getPerformanceInstance(frame());
   if (performance)
     performance->addFirstPaintTiming(m_firstPaint);
 
-  TRACE_EVENT_INSTANT1("blink.user_timing,rail", "firstPaint",
+  TRACE_EVENT_INSTANT1("rail,devtools.timeline", "firstPaint",
                        TRACE_EVENT_SCOPE_PROCESS, "frame", frame());
 }
 
 void PaintTiming::setFirstContentfulPaint(double stamp) {
   if (m_firstContentfulPaint != 0.0)
     return;
   setFirstPaint(stamp);
   m_firstContentfulPaint = stamp;
   Performance* performance = getPerformanceInstance(frame());
   if (performance)
     performance->addFirstContentfulPaintTiming(m_firstContentfulPaint);
-  TRACE_EVENT_INSTANT1("blink.user_timing,rail", "firstContentfulPaint",
+  TRACE_EVENT_INSTANT1("rail,devtools.timeline", "firstContentfulPaint",

[pfeldman, 2017/04/07 19:02:33]

I only found this one mentioned in catapult, but I did not find the category
check there, only the name one. So is this part safe to land then?

                        TRACE_EVENT_SCOPE_PROCESS, "frame", frame());
 }
 
 }  // namespace blink