Timeline addTraceProvider API

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

Index: third_party/WebKit/Source/devtools/front_end/timeline/TimelinePanel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/timeline/TimelinePanel.js b/third_party/WebKit/Source/devtools/front_end/timeline/TimelinePanel.js
index 63a911ee61f34234a7b5a5bea3198437b5bf6f0e..ad53fdb05c20fdb4f93dac216a8613c33191321c 100644
--- a/third_party/WebKit/Source/devtools/front_end/timeline/TimelinePanel.js
+++ b/third_party/WebKit/Source/devtools/front_end/timeline/TimelinePanel.js
@@ -67,6 +67,16 @@ WebInspector.TimelinePanel = function()
     if (Runtime.experiments.isEnabled("cpuThrottling"))
         this._cpuThrottlingManager = new WebInspector.CPUThrottlingManager();
 
+    // Create extension trace providers.
+    this._traceProvidersById = {};

[caseq, 2016/06/21 07:29:51]

We prefer using maps in the new code, i.e.

/**
  * @type {!Map<string, !WebInspector.TraceProvider>}
  *
this._traceProvidersById = new Map();

+    this._captureExtensionSettings = {};

[caseq, 2016/06/21 07:29:51]

ditto.

+    var extensionTraceProviders = WebInspector.extensionServer.traceProviders();
+    for (var i = 0; i < extensionTraceProviders.length; ++i) {
+        var provider = extensionTraceProviders[i];

[caseq, 2016/06/21 07:29:51]

nit: for (var provider of extensionTraceProviders) { ...

+        this.addTraceProvider(provider);
+        this._captureExtensionSettings[provider.id] = WebInspector.settings.createSetting(provider.categoryName, false);
+    }
+
     /** @type {!Array.<!WebInspector.TimelineModeView>} */
     this._currentViews = [];
 
@@ -162,6 +172,28 @@ WebInspector.TimelinePanel.headerHeight = 20;
 
 WebInspector.TimelinePanel.prototype = {
     /**
+     * @return {!Object.<string, !WebInspector.ExtensionTraceProvider>}
+     */
+    get traceProvidersById()

[caseq, 2016/06/21 07:29:51]

do you need to expose this? Also, we avoid getters in the new code, just use
functions.

+    {
+        return this._traceProvidersById;
+    },
+
+    addTraceProvider: function(provider)
+    {
+        this._traceProvidersById[provider.id] = provider;
+    },
+
+     /**
+     * @param {string} id
+     * @return {!WebInspector.ExtensionTraceProvider}
+     */
+    getTraceProvider: function(id)

[caseq, 2016/06/21 07:29:51]

not sure you need to expose any of these (also: please drop "get" prefixes on
getters and prefix with underscores for "private" methods)

+    {
+        return this.traceProvidersById[id];
+    },
+
+    /**
      * @override
      * @return {?WebInspector.SearchableView}
      */
@@ -390,6 +422,11 @@ WebInspector.TimelinePanel.prototype = {
                 WebInspector.UIString("Memory"), this._captureMemorySetting, WebInspector.UIString("Capture memory information on every timeline event.")));
             this._panelToolbar.appendToolbarItem(this._createSettingCheckbox(
                 WebInspector.UIString("Paint"), this._captureLayersAndPicturesSetting, WebInspector.UIString("Capture graphics layer positions and rasterization draw calls. (Has large performance overhead)")));
+            for (var s in this._captureExtensionSettings) {

[caseq, 2016/06/21 07:29:51]

I guess you also want to handle TraceProviderAdded to handle the trace providers
added after timeline panel is instantiated.

+                this._panelToolbar.appendToolbarItem(this._createSettingCheckbox(
+                    WebInspector.UIString(this._traceProvidersById[s].categoryName), this._captureExtensionSettings[s], WebInspector.UIString(this._traceProvidersById[s].categoryTooltip)));
+            }
+
         } else {
             this._panelToolbar.appendToolbarItem(screenshotCheckbox);
         }