DevTools: Show FMP markers on timeline experiment

third_party/WebKit/Source/devtools/front_end/timeline/TimelineController.js

 // Copyright 2016 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.
 
 /**
  * @implements {SDK.TargetManager.Observer}
  * @implements {SDK.TracingManagerClient}
  * @unrestricted
  */
 Timeline.TimelineController = class {
@@ skipping 26 matching lines @@
     function disabledByDefault(category) {
       return 'disabled-by-default-' + category;
     }
     const categoriesArray = [
       '-*', 'devtools.timeline', 'v8.execute', disabledByDefault('devtools.timeline'),
       disabledByDefault('devtools.timeline.frame'), SDK.TracingModel.TopLevelEventCategory,
       TimelineModel.TimelineModel.Category.Console, TimelineModel.TimelineModel.Category.UserTiming
     ];
     categoriesArray.push(TimelineModel.TimelineModel.Category.LatencyInfo);
 
+    if (Runtime.experiments.isEnabled('timelineShowFMP'))
+      categoriesArray.push('loading');
     if (Runtime.experiments.isEnabled('timelineV8RuntimeCallStats') && options.enableJSSampling)
       categoriesArray.push(disabledByDefault('v8.runtime_stats_sampling'));
     if (Runtime.experiments.isEnabled('timelineTracingJSProfile') && options.enableJSSampling) {
       categoriesArray.push(disabledByDefault('v8.cpu_profiler'));
       if (Common.moduleSetting('highResolutionCpuProfiling').get())
         categoriesArray.push(disabledByDefault('v8.cpu_profiler.hires'));
     }
     categoriesArray.push(disabledByDefault('devtools.timeline.stack'));
     if (Runtime.experiments.isEnabled('timelineInvalidationTracking'))
       categoriesArray.push(disabledByDefault('devtools.timeline.invalidationTracking'));
@@ skipping 222 matching lines @@
 };
 
 /**
  * @typedef {!{
  *   enableJSSampling: (boolean|undefined),
  *   capturePictures: (boolean|undefined),
  *   captureFilmStrip: (boolean|undefined)
  * }}
  */
 Timeline.TimelineController.RecordingOptions;