DevTools: Initial implementation of line-level CPU profile.

third_party/WebKit/Source/devtools/front_end/timeline/module.json

 {
     "extensions": [
         {
             "type": "@WebInspector.PanelFactory",
             "name": "timeline",
             "title": "Timeline",
             "order": 50,
             "className": "WebInspector.TimelinePanelFactory"
         },
         {
             "type": "setting",
             "category": "Profiler",
             "title": "Hide chrome frame in Layers view",
             "settingName": "frameViewerHideChromeWindow",
             "settingType": "boolean",
             "defaultValue": false
         },
         {
             "type": "@WebInspector.QueryParamHandler",
             "name": "loadTimelineFromURL",
             "className": "WebInspector.LoadTimelineHandler"
         },
         {
+            "type": "line-marker-decorator-performance",
+            "className": "WebInspector.TimelineUIUtils.PerformanceLineMarkerDecorator"
+        },
+        {
             "type": "@WebInspector.ActionDelegate",
             "actionId": "timeline.toggle-recording",
             "iconClass": "record-toolbar-item",
             "contextTypes": ["WebInspector.TimelinePanel"],
             "className": "WebInspector.TimelinePanel.ActionDelegate",
             "bindings": [
                 {
                     "platform": "windows,linux",
                     "shortcut": "Ctrl+E"
                 },
@@ skipping 89 matching lines @@
         "PaintProfilerView.js",
         "TimelinePanel.js"
     ],
     "resources": [
         "invalidationsTree.css",
         "timelineFlamechartPopover.css",
         "timelinePanel.css",
         "timelineStatusDialog.css"
     ]
 }