DevTools: eliminate ToolbarButton.setState method; cleanup toolbar.css

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

 {
     "extensions": [
         {
             "type": "view",
             "location": "panel",
             "id": "timeline",
             "title": "Timeline",
             "order": 50,
             "className": "WebInspector.TimelinePanel"
         },
@@ skipping 17 matching lines @@
         },
         {
             "type": "context-menu-item",
             "location": "timelineMenu/open",
             "actionId": "timeline.save-to-file"
         },
         {
             "type": "@WebInspector.ActionDelegate",
             "actionId": "timeline.toggle-recording",
             "iconClass": "record-toolbar-item",
+            "toggledIconClass": "active-recording-toolbar-item",
             "contextTypes": ["WebInspector.TimelinePanel"],
             "className": "WebInspector.TimelinePanel.ActionDelegate",
             "options": [
                 { "value": true, "title": "Record" },
                 { "value": false, "title": "Stop" }
             ],
             "bindings": [
                 {
                     "platform": "windows,linux",
                     "shortcut": "Ctrl+E"
@@ skipping 85 matching lines @@
         "TimelinePanel.js"
     ],
     "resources": [
         "invalidationsTree.css",
         "timelineFlamechartPopover.css",
         "timelinePanel.css",
         "timelinePaintProfiler.css",
         "timelineStatusDialog.css"
     ]
 }