[DevTools] Add "never show" link to emulation warning.

Source/devtools/front_end/toolbox/ResponsiveDesignView.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.VBox}
  * @implements {WebInspector.OverridesSupport.PageResizer}
  * @implements {WebInspector.TargetManager.Observer}
  * @param {!WebInspector.InspectedPagePlaceholder} inspectedPagePlaceholder
@@ skipping 15 matching lines @@
 
     this._mediaInspectorContainer = this._canvasContainer.element.createChild("div", "responsive-design-media-container");
     this._mediaInspector = new WebInspector.MediaQueryInspector();
     this._updateMediaQueryInspector();
 
     this._canvas = this._canvasContainer.element.createChild("canvas", "fill responsive-design-canvas");
 
     this._warningMessage = this._canvasContainer.element.createChild("div", "responsive-design-warning hidden");
     this._warningMessage.createChild("div", "warning-icon-small");
     this._warningMessage.createChild("span");
+    var warningDisableButton = this._warningMessage.createChild("div", "disable-warning");
+    warningDisableButton.textContent = WebInspector.UIString("Never show");
+    warningDisableButton.addEventListener("click", this._disableOverridesWarnings.bind(this), false);
     var warningCloseButton = this._warningMessage.createChild("div", "close-button");
     warningCloseButton.addEventListener("click", WebInspector.overridesSupport.clearWarningMessage.bind(WebInspector.overridesSupport), false);
     WebInspector.overridesSupport.addEventListener(WebInspector.OverridesSupport.Events.OverridesWarningUpdated, this._overridesWarningUpdated, this);
+    WebInspector.settings.disableOverridesWarning.addChangeListener(this._overridesWarningUpdated, this);
 
     this._slidersContainer = this._canvasContainer.element.createChild("div", "vbox responsive-design-sliders-container");
     var hbox = this._slidersContainer.createChild("div", "hbox flex-auto");
     this._heightSliderContainer = this._slidersContainer.createChild("div", "hbox responsive-design-slider-height");
     this._pageContainer = hbox.createChild("div", "vbox flex-auto");
     this._widthSliderContainer = hbox.createChild("div", "vbox responsive-design-slider-width");
 
     this._widthSlider = this._widthSliderContainer.createChild("div", "responsive-design-slider-thumb");
     this._widthSlider.createChild("div", "responsive-design-thumb-handle");
     this._createResizer(this._widthSlider, false);
@@ skipping 628 matching lines @@
     _updateMediaQueryInspectorButton: function(event)
     {
         var count = /** @type {number} */ (event.data);
         this._toggleMediaInspectorButton.setEnabled(!!count);
         this._toggleMediaInspectorButton.title = !count ? WebInspector.UIString("Media queries not found") :
             WebInspector.UIString((count === 1 ? "%d media query found" : "%d media queries found"), count);
     },
 
     _overridesWarningUpdated: function()
     {
-        var message = WebInspector.overridesSupport.warningMessage();
-        if (this._warningMessage.querySelector("span").textContent === message)
+        var message = WebInspector.settings.disableOverridesWarning.get() ? "" : WebInspector.overridesSupport.warningMessage();
+        if (this._warning === message)
             return;
+        this._warning = message;
         this._warningMessage.classList.toggle("hidden", !message);
         this._warningMessage.querySelector("span").textContent = message;
         this._invalidateCache();
         this.onResize();
     },
 
+    _disableOverridesWarnings: function()
+    {
+        WebInspector.settings.disableOverridesWarning.set(true);
+    },
+
     _showEmulationInDrawer: function()
     {
         WebInspector.Revealer.reveal(WebInspector.overridesSupport);
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _viewportChanged: function(event)
     {
@@ skipping 37 matching lines @@
                 value = Math.min(this._viewport.maximumPageScaleFactor, value);
                 value = Math.max(this._viewport.minimumPageScaleFactor, value)
                 this._target.pageAgent().setPageScaleFactor(value);
             }
             finishCallback();
         }
     },
 
     __proto__: WebInspector.VBox.prototype
 };