Refactored the attributes modules of extension_view and web_view into guest_view_attributes.js.

extensions/renderer/resources/guest_view/web_view/web_view_attributes.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.
 
 // This module implements the attributes of the <webview> tag.
 
-var GuestViewInternal =
-    require('binding').Binding.create('guestViewInternal').generate();
+var GuestViewAttributes = require('guestViewAttributes').GuestViewAttributes;
 var WebViewImpl = require('webView').WebViewImpl;
 var WebViewConstants = require('webViewConstants').WebViewConstants;
 var WebViewInternal = require('webViewInternal').WebViewInternal;
 
 // -----------------------------------------------------------------------------
-// Attribute objects.
+// AllowScalingAttribute object.
 
-// Default implementation of a WebView attribute.
-function WebViewAttribute(name, webViewImpl) {
-  this.name = name;
-  this.webViewImpl = webViewImpl;
-  this.ignoreMutation = false;
-
-  this.defineProperty();
+// Attribute that specifies whether scaling is allowed in the webview.
+function AllowScalingAttribute(view) {
+  GuestViewAttributes.BooleanAttribute.call(
+      this, WebViewConstants.ATTRIBUTE_ALLOWSCALING, view);
 }
 
-// Retrieves and returns the attribute's value.
-WebViewAttribute.prototype.getValue = function() {
-  return this.webViewImpl.element.getAttribute(this.name) || '';
+AllowScalingAttribute.prototype.__proto__ =
+    GuestViewAttributes.BooleanAttribute.prototype;
+
+AllowScalingAttribute.prototype.handleMutation = function(oldValue, newValue) {
+  if (!this.view.guest.getId())
+  return;
+
+  WebViewInternal.setAllowScaling(this.view.guest.getId(), this.getValue());
 };
 
-// Sets the attribute's value.
-WebViewAttribute.prototype.setValue = function(value) {
-  this.webViewImpl.element.setAttribute(this.name, value || '');
-};
+// -----------------------------------------------------------------------------
+// AllowTransparencyAttribute object.
 
-// Changes the attribute's value without triggering its mutation handler.
-WebViewAttribute.prototype.setValueIgnoreMutation = function(value) {
-  this.ignoreMutation = true;
-  this.setValue(value);
-  this.ignoreMutation = false;
+// Attribute that specifies whether transparency is allowed in the webview.
+function AllowTransparencyAttribute(view) {
+  GuestViewAttributes.BooleanAttribute.call(
+      this, WebViewConstants.ATTRIBUTE_ALLOWTRANSPARENCY, view);
 }
 
-// Defines this attribute as a property on the webview node.
-WebViewAttribute.prototype.defineProperty = function() {
-  Object.defineProperty(this.webViewImpl.element, this.name, {
-    get: function() {
-      return this.getValue();
-    }.bind(this),
-    set: function(value) {
-      this.setValue(value);
-    }.bind(this),
-    enumerable: true
-  });
-};
-
-// Called when the attribute's value changes.
-WebViewAttribute.prototype.maybeHandleMutation = function(oldValue, newValue) {
-  if (this.ignoreMutation) {
-    return;
-  }
-
-  this.handleMutation(oldValue, newValue);
-};
-
-// Called when a change that isn't ignored occurs to the attribute's value.
-WebViewAttribute.prototype.handleMutation = function(oldValue, newValue) {};
-
-// Called when the <webview> element is attached to the DOM tree.
-WebViewAttribute.prototype.attach = function() {};
-
-// Called when the <webview> element is detached from the DOM tree.
-WebViewAttribute.prototype.detach = function() {};
-
-// An attribute that is treated as a Boolean.
-function BooleanAttribute(name, webViewImpl) {
-  WebViewAttribute.call(this, name, webViewImpl);
-}
-
-BooleanAttribute.prototype.__proto__ = WebViewAttribute.prototype;
-
-BooleanAttribute.prototype.getValue = function() {
-  return this.webViewImpl.element.hasAttribute(this.name);
-};
-
-BooleanAttribute.prototype.setValue = function(value) {
-  if (!value) {
-    this.webViewImpl.element.removeAttribute(this.name);
-  } else {
-    this.webViewImpl.element.setAttribute(this.name, '');
-  }
-};
-
-// Attribute that specifies whether transparency is allowed in the webview.
-function AllowTransparencyAttribute(webViewImpl) {
-  BooleanAttribute.call(
-      this, WebViewConstants.ATTRIBUTE_ALLOWTRANSPARENCY, webViewImpl);
-}
-
-AllowTransparencyAttribute.prototype.__proto__ = BooleanAttribute.prototype;
+AllowTransparencyAttribute.prototype.__proto__ =
+    GuestViewAttributes.BooleanAttribute.prototype;
 
 AllowTransparencyAttribute.prototype.handleMutation = function(oldValue,
                                                                newValue) {
-  if (!this.webViewImpl.guest.getId()) {
+  if (!this.view.guest.getId())
     return;
-  }
 
-  WebViewInternal.setAllowTransparency(this.webViewImpl.guest.getId(),
+  WebViewInternal.setAllowTransparency(this.view.guest.getId(),
                                        this.getValue());
 };
 
-// Attribute that specifies whether transparency is allowed in the webview.
-function AllowScalingAttribute(webViewImpl) {
-  BooleanAttribute.call(
-      this, WebViewConstants.ATTRIBUTE_ALLOWSCALING, webViewImpl);
+// -----------------------------------------------------------------------------
+// AutosizeDimensionAttribute object.
+
+// Attribute used to define the demension limits of autosizing.
+function AutosizeDimensionAttribute(name, view) {
+  GuestViewAttributes.IntegerAttribute.call(this, name, view);
 }
 
-AllowScalingAttribute.prototype.__proto__ = BooleanAttribute.prototype;
-
-AllowScalingAttribute.prototype.handleMutation = function(oldValue,
-                                                          newValue) {
-  if (!this.webViewImpl.guest.getId()) {
-    return;
-  }
-
-  WebViewInternal.setAllowScaling(this.webViewImpl.guest.getId(),
-                                  this.getValue());
-};
-
-// Attribute used to define the demension limits of autosizing.
-function AutosizeDimensionAttribute(name, webViewImpl) {
-  WebViewAttribute.call(this, name, webViewImpl);
-}
-
-AutosizeDimensionAttribute.prototype.__proto__ = WebViewAttribute.prototype;
-
-AutosizeDimensionAttribute.prototype.getValue = function() {
-  return parseInt(this.webViewImpl.element.getAttribute(this.name)) || 0;
-};
+AutosizeDimensionAttribute.prototype.__proto__ =
+    GuestViewAttributes.IntegerAttribute.prototype;
 
 AutosizeDimensionAttribute.prototype.handleMutation = function(
     oldValue, newValue) {
-  if (!this.webViewImpl.guest.getId()) {
+  if (!this.view.guest.getId())
     return;
-  }
-  this.webViewImpl.guest.setSize({
-    'enableAutoSize': this.webViewImpl.attributes[
-        WebViewConstants.ATTRIBUTE_AUTOSIZE].getValue(),
+
+  this.view.guest.setSize({
+    'enableAutoSize': this.view.attributes[
+      WebViewConstants.ATTRIBUTE_AUTOSIZE].getValue(),
     'min': {
-      'width': this.webViewImpl.attributes[
+      'width': this.view.attributes[
           WebViewConstants.ATTRIBUTE_MINWIDTH].getValue(),
-      'height': this.webViewImpl.attributes[
+      'height': this.view.attributes[
           WebViewConstants.ATTRIBUTE_MINHEIGHT].getValue()
     },
     'max': {
-      'width': this.webViewImpl.attributes[
+      'width': this.view.attributes[
           WebViewConstants.ATTRIBUTE_MAXWIDTH].getValue(),
-      'height': this.webViewImpl.attributes[
+      'height': this.view.attributes[
           WebViewConstants.ATTRIBUTE_MAXHEIGHT].getValue()
     }
   });
   return;
 };
 
+// -----------------------------------------------------------------------------
+// AutosizeAttribute object.
+
 // Attribute that specifies whether the webview should be autosized.
-function AutosizeAttribute(webViewImpl) {
-  BooleanAttribute.call(this, WebViewConstants.ATTRIBUTE_AUTOSIZE, webViewImpl);
+function AutosizeAttribute(view) {
+  GuestViewAttributes.BooleanAttribute.call(
+      this, WebViewConstants.ATTRIBUTE_AUTOSIZE, view);
 }
 
-AutosizeAttribute.prototype.__proto__ = BooleanAttribute.prototype;
+AutosizeAttribute.prototype.__proto__ =
+    GuestViewAttributes.BooleanAttribute.prototype;
 
 AutosizeAttribute.prototype.handleMutation =
     AutosizeDimensionAttribute.prototype.handleMutation;
 
+// -----------------------------------------------------------------------------
+// NameAttribute object.
+
 // Attribute that sets the guest content's window.name object.
-function NameAttribute(webViewImpl) {
-  WebViewAttribute.call(this, WebViewConstants.ATTRIBUTE_NAME, webViewImpl);
+function NameAttribute(view) {
+  GuestViewAttributes.Attribute.call(
+      this, WebViewConstants.ATTRIBUTE_NAME, view);
 }
 
-NameAttribute.prototype.__proto__ = WebViewAttribute.prototype
+NameAttribute.prototype.__proto__ = GuestViewAttributes.Attribute.prototype
 
 NameAttribute.prototype.handleMutation = function(oldValue, newValue) {
   oldValue = oldValue || '';
   newValue = newValue || '';
-  if (oldValue === newValue || !this.webViewImpl.guest.getId()) {
+  if (oldValue === newValue || !this.view.guest.getId())
     return;
-  }
 
-  WebViewInternal.setName(this.webViewImpl.guest.getId(), newValue);
+  WebViewInternal.setName(this.view.guest.getId(), newValue);
 };
 
 NameAttribute.prototype.setValue = function(value) {
   value = value || '';
-  if (value === '') {
-    this.webViewImpl.element.removeAttribute(this.name);
-  } else {
-    this.webViewImpl.element.setAttribute(this.name, value);
-  }
+  if (value === '')
+    this.view.element.removeAttribute(this.name);
+  else
+    this.view.element.setAttribute(this.name, value);
 };
 
+// -----------------------------------------------------------------------------
+// PartitionAttribute object.
+
 // Attribute representing the state of the storage partition.
-function PartitionAttribute(webViewImpl) {
-  WebViewAttribute.call(
-      this, WebViewConstants.ATTRIBUTE_PARTITION, webViewImpl);
+function PartitionAttribute(view) {
+  GuestViewAttributes.Attribute.call(
+      this, WebViewConstants.ATTRIBUTE_PARTITION, view);
   this.validPartitionId = true;
 }
 
-PartitionAttribute.prototype.__proto__ = WebViewAttribute.prototype;
+PartitionAttribute.prototype.__proto__ =
+    GuestViewAttributes.Attribute.prototype;
 
 PartitionAttribute.prototype.handleMutation = function(oldValue, newValue) {
   newValue = newValue || '';
 
   // The partition cannot change if the webview has already navigated.
-  if (!this.webViewImpl.attributes[
+  if (!this.view.attributes[
           WebViewConstants.ATTRIBUTE_SRC].beforeFirstNavigation) {
     window.console.error(WebViewConstants.ERROR_MSG_ALREADY_NAVIGATED);
     this.setValueIgnoreMutation(oldValue);
     return;
   }
   if (newValue == 'persist:') {
     this.validPartitionId = false;
     window.console.error(
         WebViewConstants.ERROR_MSG_INVALID_PARTITION_ATTRIBUTE);
   }
 };
 
 PartitionAttribute.prototype.detach = function() {
   this.validPartitionId = true;
 };
 
+// -----------------------------------------------------------------------------
+// SrcAttribute object.
+
 // Attribute that handles the location and navigation of the webview.
-function SrcAttribute(webViewImpl) {
-  WebViewAttribute.call(this, WebViewConstants.ATTRIBUTE_SRC, webViewImpl);
+function SrcAttribute(view) {
+  GuestViewAttributes.Attribute.call(
+      this, WebViewConstants.ATTRIBUTE_SRC, view);
   this.setupMutationObserver();
   this.beforeFirstNavigation = true;
-  this.elementAttached = false;
 }
 
-SrcAttribute.prototype.__proto__ = WebViewAttribute.prototype;
+SrcAttribute.prototype.__proto__ = GuestViewAttributes.Attribute.prototype;
 
 SrcAttribute.prototype.setValueIgnoreMutation = function(value) {
-  WebViewAttribute.prototype.setValueIgnoreMutation.call(this, value);
+  GuestViewAttributes.Attribute.prototype.setValueIgnoreMutation.call(
+      this, value);
   // takeRecords() is needed to clear queued up src mutations. Without it, it is
   // possible for this change to get picked up asyncronously by src's mutation
   // observer |observer|, and then get handled even though we do not want to
   // handle this mutation.
   this.observer.takeRecords();
 }
 
 SrcAttribute.prototype.handleMutation = function(oldValue, newValue) {
   // Once we have navigated, we don't allow clearing the src attribute.
   // Once <webview> enters a navigated state, it cannot return to a
   // placeholder state.
   if (!newValue && oldValue) {
     // src attribute changes normally initiate a navigation. We suppress
     // the next src attribute handler call to avoid reloading the page
     // on every guest-initiated navigation.
     this.setValueIgnoreMutation(oldValue);
     return;
   }
   this.parse();
 };
 
 SrcAttribute.prototype.attach = function() {
-  this.elementAttached = true;
   this.parse();
 };
 
 SrcAttribute.prototype.detach = function() {
   this.beforeFirstNavigation = true;
-  this.elementAttached = false;
 };
 
 // The purpose of this mutation observer is to catch assignment to the src
 // attribute without any changes to its value. This is useful in the case
 // where the webview guest has crashed and navigating to the same address
 // spawns off a new process.
 SrcAttribute.prototype.setupMutationObserver =
     function() {
   this.observer = new MutationObserver(function(mutations) {
     $Array.forEach(mutations, function(mutation) {
       var oldValue = mutation.oldValue;
       var newValue = this.getValue();
       if (oldValue != newValue) {
         return;
       }
       this.handleMutation(oldValue, newValue);
     }.bind(this));
   }.bind(this));
   var params = {
     attributes: true,
     attributeOldValue: true,
     attributeFilter: [this.name]
   };
-  this.observer.observe(this.webViewImpl.element, params);
+  this.observer.observe(this.view.element, params);
 };
 
 SrcAttribute.prototype.parse = function() {
-  if (!this.elementAttached ||
-      !this.webViewImpl.attributes[
+  if (!this.view.elementAttached ||
+      !this.view.attributes[
           WebViewConstants.ATTRIBUTE_PARTITION].validPartitionId ||
       !this.getValue()) {
     return;
   }
 
-  if (!this.webViewImpl.guest.getId()) {
+  if (!this.view.guest.getId()) {
     if (this.beforeFirstNavigation) {
       this.beforeFirstNavigation = false;
-      this.webViewImpl.createGuest();
+      this.view.createGuest();
     }
     return;
   }
 
-  // Navigate to |src|.
-  WebViewInternal.navigate(this.webViewImpl.guest.getId(), this.getValue());
+  WebViewInternal.navigate(this.view.guest.getId(), this.getValue());
 };
 
 // -----------------------------------------------------------------------------
 
 // Sets up all of the webview attributes.
 WebViewImpl.prototype.setupWebViewAttributes = function() {
   this.attributes = {};
 
+  this.attributes[WebViewConstants.ATTRIBUTE_ALLOWSCALING] =
+      new AllowScalingAttribute(this);
   this.attributes[WebViewConstants.ATTRIBUTE_ALLOWTRANSPARENCY] =
       new AllowTransparencyAttribute(this);
-  this.attributes[WebViewConstants.ATTRIBUTE_ALLOWSCALING] =
-      new AllowScalingAttribute(this);
   this.attributes[WebViewConstants.ATTRIBUTE_AUTOSIZE] =
       new AutosizeAttribute(this);
   this.attributes[WebViewConstants.ATTRIBUTE_NAME] =
       new NameAttribute(this);
   this.attributes[WebViewConstants.ATTRIBUTE_PARTITION] =
       new PartitionAttribute(this);
   this.attributes[WebViewConstants.ATTRIBUTE_SRC] =
       new SrcAttribute(this);
 
   var autosizeAttributes = [WebViewConstants.ATTRIBUTE_MAXHEIGHT,
                             WebViewConstants.ATTRIBUTE_MAXWIDTH,
                             WebViewConstants.ATTRIBUTE_MINHEIGHT,
                             WebViewConstants.ATTRIBUTE_MINWIDTH];
   for (var i = 0; autosizeAttributes[i]; ++i) {
     this.attributes[autosizeAttributes[i]] =
         new AutosizeDimensionAttribute(autosizeAttributes[i], this);
   }
 };