DevTools: Add dark theme hidden experiment

third_party/WebKit/Source/devtools/front_end/main/Main.js

 /*
  * Copyright (C) 2006, 2007, 2008 Apple Inc.  All rights reserved.
  * Copyright (C) 2007 Matt Lilek (pewtermoose@gmail.com).
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 89 matching lines @@
     /**
      * @param {!Object<string, string>} prefs
      */
     _initializeExperiments: function(prefs)
     {
         Runtime.experiments.register("accessibilityInspection", "Accessibility Inspection");
         Runtime.experiments.register("animationInspection", "Animation Inspection");
         Runtime.experiments.register("applyCustomStylesheet", "Allow custom UI themes");
         Runtime.experiments.register("blackboxJSFramesOnTimeline", "Blackbox JavaScript frames on Timeline", true);
         Runtime.experiments.register("colorContrastRatio", "Contrast ratio line in color picker", true);
+        Runtime.experiments.register("darkTheme", "Dark theme", true);
         Runtime.experiments.register("deviceMode", "Device mode", true);
         Runtime.experiments.register("emptySourceMapAutoStepping", "Empty sourcemap auto-stepping");
         Runtime.experiments.register("fileSystemInspection", "FileSystem inspection");
         Runtime.experiments.register("gpuTimeline", "GPU data on timeline", true);
         Runtime.experiments.register("inputEventsOnTimelineOverview", "Input events on Timeline overview", true);
         Runtime.experiments.register("layersPanel", "Layers panel");
         Runtime.experiments.register("layoutEditor", "Layout editor", true);
         Runtime.experiments.register("materialDesign", "Material design");
         Runtime.experiments.register("multipleTimelineViews", "Multiple main views on Timeline", true);
         Runtime.experiments.register("networkRequestHeadersFilterInDetailsView", "Network request headers filter in details view", true);
@@ skipping 40 matching lines @@
     _createAppUI: function()
     {
         console.timeStamp("Main._createApp");
 
         // Request filesystems early, we won't create connections until callback is fired. Things will happen in parallel.
         WebInspector.isolatedFileSystemManager = new WebInspector.IsolatedFileSystemManager();
         WebInspector.isolatedFileSystemManager.initialize(this._didInitializeFileSystemManager.bind(this));
 
         WebInspector.initializeUIUtils(window);
         WebInspector.installComponentRootStyles(/** @type {!Element} */ (document.body));
+        if (Runtime.experiments.isEnabled("darkTheme")) {
+            document.body.classList.add("dark-theme");
+        }
 
         this._addMainEventListeners(document);
 
         var canDock = !!Runtime.queryParam("can_dock");
         WebInspector.zoomManager = new WebInspector.ZoomManager(window, InspectorFrontendHost);
         WebInspector.inspectorView = new WebInspector.InspectorView();
         WebInspector.ContextMenu.initialize();
         WebInspector.ContextMenu.installHandler(document);
         WebInspector.Tooltip.installHandler(document);
         WebInspector.dockController = new WebInspector.DockController(canDock);
@@ skipping 864 matching lines @@
      */
     willHide: function()
     {
         this._hideCallback.call(null);
     },
 
     __proto__: WebInspector.VBox.prototype
 }
 
 new WebInspector.Main();