Web MIDI API: disallow to add custom exceptions on content settings UI

chrome/browser/resources/options/content_settings_exceptions_area.js

 // Copyright (c) 2012 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.
 
 cr.define('options.contentSettings', function() {
   /** @const */ var ControlledSettingIndicator =
                     options.ControlledSettingIndicator;
   /** @const */ var InlineEditableItemList = options.InlineEditableItemList;
   /** @const */ var InlineEditableItem = options.InlineEditableItem;
   /** @const */ var ArrayDataModel = cr.ui.ArrayDataModel;
 
   /**
+   * Returns whether exceptions list for the type is editable.
+   *
+   * @param {string} contentType The type of the list.
+   */
+  function IsEditableType(contentType) {
+    // Exceptions of the following lists are not editable for now.
+    return !(contentType == 'notifications' ||
+             contentType == 'location' ||
+             contentType == 'fullscreen' ||
+             contentType == 'media-stream' ||
+             contentType == 'midi-sysex' ||
+             contentType == 'zoomlevels');
+  }
+
+  /**
    * Creates a new exceptions list item.
    *
    * @param {string} contentType The type of the list.
    * @param {string} mode The browser mode, 'otr' or 'normal'.
    * @param {Object} exception A dictionary that contains the data of the
    *     exception.
    * @constructor
    * @extends {options.InlineEditableItem}
    */
   function ExceptionsListItem(contentType, mode, exception) {
@@ skipping 94 matching lines @@
         var videoSettingLabel = cr.doc.createElement('span');
         videoSettingLabel.textContent = this.videoSettingForDisplay();
         videoSettingLabel.className = 'exception-setting';
         videoSettingLabel.classList.add('media-video-setting');
         videoSettingLabel.setAttribute('displaymode', 'static');
         this.contentElement.appendChild(videoSettingLabel);
       }
 
       if (this.contentType == 'zoomlevels') {
         this.deletable = true;
-        this.editable = false;
 
         var zoomLabel = cr.doc.createElement('span');
         zoomLabel.textContent = this.dataItem.zoom;
         zoomLabel.className = 'exception-setting';
         zoomLabel.setAttribute('displaymode', 'static');
         zoomLabel.setAttribute('aria-labelledby', 'exception-zoom-column');
         this.contentElement.appendChild(zoomLabel);
         this.zoomLabel = zoomLabel;
       }
 
       // Used to track whether the URL pattern in the input is valid.
       // This will be true if the browser process has informed us that the
       // current text in the input is valid. Changing the text resets this to
       // false, and getting a response from the browser sets it back to true.
       // It starts off as false for empty string (new exceptions) or true for
       // already-existing exceptions (which we assume are valid).
       this.inputValidityKnown = this.pattern;
       // This one tracks the actual validity of the pattern in the input. This
       // starts off as true so as not to annoy the user when he adds a new and
       // empty input.
       this.inputIsValid = true;
 
       this.input = input;
       this.select = select;
 
       this.updateEditables();
-
-      // Editing notifications, geolocation and media-stream is disabled for
-      // now.
-      if (this.contentType == 'notifications' ||
-          this.contentType == 'location' ||
-          this.contentType == 'media-stream') {
-        this.editable = false;
-      }
+      this.editable = this.editable && IsEditableType(this.contentType);
 
       // If the source of the content setting exception is not a user
       // preference, that source controls the exception and the user cannot edit
       // or delete it.
       var controlledBy =
           this.dataItem.source && this.dataItem.source != 'preference' ?
               this.dataItem.source : null;
 
       if (controlledBy) {
         this.setAttribute('controlled-by', controlledBy);
@@ skipping 361 matching lines @@
         if (pattern == listItem.input.value)
           listItem.setPatternValid(valid);
       }
     },
 
     /**
      * Returns whether the rows are editable in this list.
      */
     isEditable: function() {
       // Exceptions of the following lists are not editable for now.
-      return !(this.contentType == 'notifications' ||
-               this.contentType == 'location' ||
-               this.contentType == 'fullscreen' ||
-               this.contentType == 'media-stream' ||
-               this.contentType == 'zoomlevels');
+      return IsEditableType(this.contentType);
     },
 
     /**
      * Removes all exceptions from the js model.
      */
     reset: function() {
       if (this.isEditable()) {
         // The null creates the Add New Exception row.
         this.dataModel = new ArrayDataModel([null]);
       } else {
@@ skipping 114 matching lines @@
     }
   };
 
   return {
     ExceptionsListItem: ExceptionsListItem,
     ExceptionsAddRowListItem: ExceptionsAddRowListItem,
     ExceptionsList: ExceptionsList,
     ContentSettingsExceptionsArea: ContentSettingsExceptionsArea,
   };
 });