DevTools: Add TimelinePowerGraph

Source/devtools/front_end/TimelinePowerGraph.js

+// Copyright 2014 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.
+
+/**
+ * @constructor
+ * @extends {WebInspector.CountersGraph}
+ * @implements {WebInspector.TimelineModeView}
+ * @param {!WebInspector.TimelineModeViewDelegate} delegate
+ * @param {!WebInspector.TimelineModel} model
+ */
+WebInspector.TimelinePowerGraph = function(delegate, model)
+{
+    WebInspector.CountersGraph.call(this, delegate, model);
+
+    this._counter = this.createCounter(WebInspector.UIString("Power"), WebInspector.UIString("Power: %.2f\u2009watts"), "#d00");
+    WebInspector.powerProfiler.addEventListener(WebInspector.PowerProfiler.EventTypes.PowerEventRecorded, this._onRecordAdded, this);
+}
+
+WebInspector.TimelinePowerGraph.prototype = {
+    _onRecordAdded: function(event)
+    {
+        var record = event.data;
+        if (!this._previousRecord) {
+            this._previousRecord = record;
+            return;
+        }
+
+        // "value" of original PowerEvent means the average power between previous sampling to current one.
+        // Here, it is converted to average power between current sampling to next one.
+        this._counter.appendSample(this._previousRecord.timestamp, record.value);
+        this._previousRecord = record;
+        this.scheduleRefresh();
+    },
+
+    /**
+     * @param {!WebInspector.TimelineModel.Record} record
+     */
+    addRecord: function(record)
+    {
+    },
+
+    __proto__: WebInspector.CountersGraph.prototype
+}