[DevTools] Access cpu profiler only when JS capability is present.

third_party/WebKit/Source/devtools/front_end/sdk/CPUProfilerModel.js

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * 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
  * notice, this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above
  * copyright notice, this list of conditions and the following disclaimer
  * in the documentation and/or other materials provided with the
  * distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY GOOGLE INC. AND ITS CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GOOGLE INC.
  * OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
+
 /**
  * @implements {Protocol.ProfilerDispatcher}
- * @unrestricted
  */
 SDK.CPUProfilerModel = class extends SDK.SDKModel {
   /**
    * @param {!SDK.Target} target
    */
   constructor(target) {
     super(target);
     this._isRecording = false;
+    this._profilerAgent = target.profilerAgent();
     target.registerProfilerDispatcher(this);
-    target.profilerAgent().enable();
-
-    this._configureCpuProfilerSamplingInterval();
-    Common.moduleSetting('highResolutionCpuProfiling')
-        .addChangeListener(this._configureCpuProfilerSamplingInterval, this);
-  }
-
-  _configureCpuProfilerSamplingInterval() {
-    var intervalUs = Common.moduleSetting('highResolutionCpuProfiling').get() ? 100 : 1000;
-    this.target().profilerAgent().setSamplingInterval(intervalUs);
+    this._profilerAgent.enable();
+    this._debuggerModel = /** @type {!SDK.DebuggerModel} */ (target.model(SDK.DebuggerModel));
   }
 
   /**
    * @override
    * @param {string} id
    * @param {!Protocol.Debugger.Location} scriptLocation
    * @param {string=} title
    */
   consoleProfileStarted(id, scriptLocation, title) {
     this._dispatchProfileEvent(SDK.CPUProfilerModel.Events.ConsoleProfileStarted, id, scriptLocation, title);
@@ skipping 13 matching lines @@
 
   /**
    * @param {symbol} eventName
    * @param {string} id
    * @param {!Protocol.Debugger.Location} scriptLocation
    * @param {string=} title
    * @param {!Protocol.Profiler.Profile=} cpuProfile
    */
   _dispatchProfileEvent(eventName, id, scriptLocation, title, cpuProfile) {
     // Make sure ProfilesPanel is initialized and CPUProfileType is created.
-    self.runtime.loadModulePromise('profiler').then(_ => {
-      var debuggerModel =
-          /** @type {!SDK.DebuggerModel} */ (SDK.DebuggerModel.fromTarget(this.target()));
-      var debuggerLocation = SDK.DebuggerModel.Location.fromPayload(debuggerModel, scriptLocation);
+    self.runtime.loadModulePromise('profiler').then(() => {
+      var debuggerLocation = SDK.DebuggerModel.Location.fromPayload(this._debuggerModel, scriptLocation);
       var globalId = this.target().id() + '.' + id;
       var data = /** @type {!SDK.CPUProfilerModel.EventData} */ (
           {id: globalId, scriptLocation: debuggerLocation, cpuProfile: cpuProfile, title: title});
       this.dispatchEventToListeners(eventName, data);
     });
   }
 
   /**
    * @return {boolean}
    */
   isRecordingProfile() {
     return this._isRecording;
   }
 
+  /**
+   * @return {!Promise}

[alph, 2017/02/28 23:59:13]

Why promise? It's a sync function

[dgozman, 2017/03/01 00:18:41]

Correct, removed the promise.

+   */
   startRecording() {
     this._isRecording = true;
-    this.target().profilerAgent().start();
     Host.userMetrics.actionTaken(Host.UserMetrics.Action.ProfilesCPUProfileTaken);
+    var intervalUs = Common.moduleSetting('highResolutionCpuProfiling').get() ? 100 : 1000;
+    this._profilerAgent.setSamplingInterval(intervalUs);
+    return this._profilerAgent.start();
   }
 
   /**
    * @return {!Promise.<?Protocol.Profiler.Profile>}
    */
   stopRecording() {
     /**
      * @param {?Protocol.Error} error
      * @param {?Protocol.Profiler.Profile} profile
      * @return {?Protocol.Profiler.Profile}
      */
     function extractProfile(error, profile) {
       return !error && profile ? profile : null;
     }
     this._isRecording = false;
-    return this.target().profilerAgent().stop(extractProfile);
+    return this._profilerAgent.stop(extractProfile);
   }
 
   /**
-   * @override
+   * @return {!Promise}
    */
-  dispose() {
-    Common.moduleSetting('highResolutionCpuProfiling')
-        .removeChangeListener(this._configureCpuProfilerSamplingInterval, this);
+  startPreciseCoverage() {
+    return this._profilerAgent.startPreciseCoverage();
+  }
+
+  /**
+   * @return {!Promise<!Array<!Protocol.Profiler.ScriptCoverage>>}
+   */
+  takePreciseCoverage() {
+    return this._profilerAgent.takePreciseCoverage((error, coverage) => error ? [] : coverage);
+  }
+
+  /**
+   * @return {!Promise}
+   */
+  stopPreciseCoverage() {
+    return this._profilerAgent.stopPreciseCoverage();
   }
 };
 
-// TODO(dgozman): should be JS.
-SDK.SDKModel.register(SDK.CPUProfilerModel, SDK.Target.Capability.None);
+SDK.SDKModel.register(SDK.CPUProfilerModel, SDK.Target.Capability.JS);
 
 /** @enum {symbol} */
 SDK.CPUProfilerModel.Events = {
   ConsoleProfileStarted: Symbol('ConsoleProfileStarted'),
   ConsoleProfileFinished: Symbol('ConsoleProfileFinished')
 };
 
 /** @typedef {!{id: string, scriptLocation: !SDK.DebuggerModel.Location, title: (string|undefined), cpuProfile: (!Protocol.Profiler.Profile|undefined)}} */
 SDK.CPUProfilerModel.EventData;