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;
@@ skipping 134 matching lines @@
       // 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.
+      // Editing notifications, geolocation, media-stream, and midi-sysex is
+      // disabled for now.
       if (this.contentType == 'notifications' ||
           this.contentType == 'location' ||
-          this.contentType == 'media-stream') {
+          this.contentType == 'media-stream' ||
+          this.contentType == 'midi-sysex') {

[Dan Beam, 2015/03/30 22:10:27]

any idea why zoomlevels isn't in this list?  if it was, we could just say:

  this.editable = this.isEditable();

or something

         this.editable = false;
       }
 
       // 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;
 
@@ skipping 367 matching lines @@
 
     /**
      * 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 == 'midi-sysex' ||
                this.contentType == 'zoomlevels');
     },
 
     /**
      * 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]);
@@ skipping 115 matching lines @@
     }
   };
 
   return {
     ExceptionsListItem: ExceptionsListItem,
     ExceptionsAddRowListItem: ExceptionsAddRowListItem,
     ExceptionsList: ExceptionsList,
     ContentSettingsExceptionsArea: ContentSettingsExceptionsArea,
   };
 });