Long tasks: add a trace event for long tasks

third_party/WebKit/Source/core/timing/Performance.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 28 matching lines @@
 #include "core/frame/DOMWindow.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/UseCounter.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/loader/DocumentLoader.h"
 #include "core/origin_trials/OriginTrials.h"
 #include "core/timing/PerformanceTiming.h"
 #include "platform/loader/fetch/ResourceTimingInfo.h"
 #include "platform/RuntimeEnabledFeatures.h"
 
-static const double kLongTaskThreshold = 0.05;
+static const double kLongTaskObserverThreshold = 0.05;
 
 static const char kUnknownAttribution[] = "unknown";
 static const char kAmbiguousAttribution[] = "multiple-contexts";
 static const char kSameOriginAttribution[] = "same-origin";
 static const char kSameOriginSelfAttribution[] = "self";
 static const char kSameOriginAncestorAttribution[] = "same-origin-ancestor";
 static const char kSameOriginDescendantAttribution[] = "same-origin-descendant";
 static const char kCrossOriginAncestorAttribution[] = "cross-origin-ancestor";
 static const char kCrossOriginDescendantAttribution[] =
     "cross-origin-descendant";
@@ skipping 91 matching lines @@
 
 void Performance::UpdateLongTaskInstrumentation() {
   DCHECK(GetFrame());
   if (!GetFrame()->GetDocument())
     return;
 
   if (HasObserverFor(PerformanceEntry::kLongTask)) {
     UseCounter::Count(&GetFrame()->LocalFrameRoot(),
                       WebFeature::kLongTaskObserver);
     GetFrame()->GetPerformanceMonitor()->Subscribe(
-        PerformanceMonitor::kLongTask, kLongTaskThreshold, this);
+        PerformanceMonitor::kLongTask, kLongTaskObserverThreshold, this);
   } else {
     GetFrame()->GetPerformanceMonitor()->UnsubscribeAll(this);
   }
 }
 
 ScriptValue Performance::toJSONForBinding(ScriptState* script_state) const {
   V8ObjectBuilder result(script_state);
   result.Add("timing", timing()->toJSONForBinding(script_state));
   result.Add("navigation", navigation()->toJSONForBinding(script_state));
   return result.GetScriptValue();
@@ skipping 85 matching lines @@
         culprit_dom_window->GetFrame()->DeprecatedLocalOwner();
     AddLongTaskTiming(
         start_time, end_time, attribution.first,
         GetFrameAttribute(frame_owner, HTMLNames::srcAttr, false),
         GetFrameAttribute(frame_owner, HTMLNames::idAttr, false),
         GetFrameAttribute(frame_owner, HTMLNames::nameAttr, true));
   }
 }
 
 }  // namespace blink