[DevTools] Add touch to sensors view.

third_party/WebKit/Source/devtools/front_end/emulation/TouchModel.js

+// Copyright 2016 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
+ * @implements {WebInspector.TargetManager.Observer}
+ */
+WebInspector.MultitargetTouchModel = function()
+{
+    this._touchEnabled = false;
+    this._touchMobile = false;
+    this._customTouchEnabled = false;
+
+    WebInspector.targetManager.observeTargets(this, WebInspector.Target.Type.Page);
+}
+
+WebInspector.MultitargetTouchModel._symbol = Symbol("MultitargetTouchModel.symbol");
+
+WebInspector.MultitargetTouchModel.prototype = {
+    /**
+     * @param {boolean} enabled
+     * @param {boolean} mobile
+     */
+    setTouchEnabled: function(enabled, mobile)
+    {
+        this._touchEnabled = enabled;
+        this._touchMobile = mobile;
+        this._updateAllTargets();
+    },
+
+    /**
+     * @param {boolean} enabled
+     */
+    setCustomTouchEnabled: function(enabled)
+    {
+        this._customTouchEnabled = enabled;
+        this._updateAllTargets();
+    },
+
+    _updateAllTargets: function()
+    {
+        for (var target of WebInspector.targetManager.targets(WebInspector.Target.Type.Page))
+            this._applyToTarget(target);
+    },
+
+    /**
+     * @param {!WebInspector.Target} target
+     */
+    _applyToTarget: function(target)
+    {
+        var current = {enabled: this._touchEnabled, configuration : this._touchMobile ? "mobile" : "desktop"};
+        if (this._customTouchEnabled)
+            current = {enabled: true, configuration: "mobile"};
+
+        var domModel = WebInspector.DOMModel.fromTarget(target);
+        var inspectModeEnabled = domModel ? domModel.inspectModeEnabled() : false;
+        if (inspectModeEnabled)
+            current = {enabled: false, configuration: "mobile"};
+
+        /**
+         * @suppressGlobalPropertiesCheck
+         */
+        const injectedFunction = function() {
+            const touchEvents = ["ontouchstart", "ontouchend", "ontouchmove", "ontouchcancel"];
+            var recepients = [window.__proto__, document.__proto__];
+            for (var i = 0; i < touchEvents.length; ++i) {
+                for (var j = 0; j < recepients.length; ++j) {
+                    if (!(touchEvents[i] in recepients[j]))
+                        Object.defineProperty(recepients[j], touchEvents[i], { value: null, writable: true, configurable: true, enumerable: true });
+                }
+            }
+        };
+
+        var symbol = WebInspector.MultitargetTouchModel._symbol;
+        var previous = target[symbol] || {enabled: false, configuration: "mobile", scriptId: ""};
+
+        if (previous.enabled === current.enabled && (!current.enabled || previous.configuration === current.configuration))
+            return;
+
+        if (previous.scriptId) {
+            target.pageAgent().removeScriptToEvaluateOnLoad(previous.scriptId);
+            target[symbol].scriptId = "";
+        }
+
+        target[symbol] = current;
+        target[symbol].scriptId = "";
+
+        if (current.enabled)
+            target.pageAgent().addScriptToEvaluateOnLoad("(" + injectedFunction.toString() + ")()", scriptAddedCallback);
+
+        /**
+         * @param {?Protocol.Error} error
+         * @param {string} scriptId
+         */
+        function scriptAddedCallback(error, scriptId)
+        {
+            (target[symbol] || {}).scriptId = error ? "" : scriptId;
+        }
+
+        target.emulationAgent().setTouchEmulationEnabled(current.enabled, current.configuration);
+    },
+
+    /**
+     * @param {!WebInspector.Event} event
+     */
+    _inspectModeToggled: function(event)
+    {
+        var domModel = /** @type {!WebInspector.DOMModel} */ (event.target);
+        this._applyToTarget(domModel.target());
+    },
+
+    /**
+     * @override
+     * @param {!WebInspector.Target} target
+     */
+    targetAdded: function(target)
+    {
+        var domModel = WebInspector.DOMModel.fromTarget(target);
+        if (domModel)
+            domModel.addEventListener(WebInspector.DOMModel.Events.InspectModeWillBeToggled, this._inspectModeToggled, this);
+        this._applyToTarget(target);
+    },
+
+    /**
+     * @override
+     * @param {!WebInspector.Target} target
+     */
+    targetRemoved: function(target)
+    {
+        var domModel = WebInspector.DOMModel.fromTarget(target);
+        if (domModel)
+            domModel.removeEventListener(WebInspector.DOMModel.Events.InspectModeWillBeToggled, this._inspectModeToggled, this);
+    }
+}
+
+
+/** @type {?WebInspector.MultitargetTouchModel} */
+WebInspector.MultitargetTouchModel._instance = null;
+
+/**
+ * @return {!WebInspector.MultitargetTouchModel}
+ */
+WebInspector.MultitargetTouchModel.instance = function()
+{
+    if (!WebInspector.MultitargetTouchModel._instance)
+        WebInspector.MultitargetTouchModel._instance = new WebInspector.MultitargetTouchModel();
+    return /** @type {!WebInspector.MultitargetTouchModel} */ (WebInspector.MultitargetTouchModel._instance);
+}