Improve implementation of isInstanceOf in JSONSchemaValidator.

chrome/common/extensions/api/extension.json

 [
   {
     "namespace": "extension",
     "nocompile": true,
     "dependencies": [ "tabs" ],
     "types": [
       {
         "id": "MessageSender",
         "type": "object",
         "description": "An object containing information about the script context that sent a message or request.",
@@ skipping 130 matching lines @@
                 "type": "integer",
                 "optional": true,
                 "description": "The window to restrict the search to. If omitted, returns all views."
               }
             }
           }
         ],
         "returns": {
           "type": "array",
           "description": "Array of global objects",
-          "items": { "type": "object", "isInstanceOf": "Window", "additionalProperties": { "type": "any" } }
+          "items": { "type": "object", "isInstanceOf": "global", "additionalProperties": { "type": "any" } }
         }
       },
       {
         "name": "getBackgroundPage",
         "type": "function",
         "description": "Returns the JavaScript 'window' object for the background page running inside the current extension. Returns null if the extension has no background page.",
         "parameters": [],
         "returns": {
-          "type": "object", "isInstanceOf": "Window", "additionalProperties": { "type": "any" }
+          "type": "object", "isInstanceOf": "global", "additionalProperties": { "type": "any" }
          }
       },
       {
         "name": "getExtensionTabs",
         "nodoc": true,
         "type": "function",
         "maximumManifestVersion": 1,
         "description": "Deprecated. Please use getViews({type: 'TAB'}). Returns an array of the JavaScript 'window' objects for each of the tabs running inside the current extension. If windowId is specified, returns only the 'window' objects of tabs attached to the specified window.",
         "parameters": [
           {"type": "integer", "name": "windowId", "optional": true}
         ],
         "returns": {
           "type": "array",
           "description": "Array of global window objects",
-          "items": { "type": "object", "isInstanceOf": "Window", "additionalProperties": { "type": "any" } }
+          "items": { "type": "object", "isInstanceOf": "global", "additionalProperties": { "type": "any" } }
         }
       },
       {
         "name": "isAllowedIncognitoAccess",
         "type": "function",
         "description": "Retrieves the state of the extension's access to Incognito-mode (as determined by the user-controlled 'Allowed in Incognito' checkbox.",
         "min_version": "12.0.706.0",
         "parameters": [
           {
             "type": "function",
@@ skipping 75 matching lines @@
         "description": "Fired when a request is sent from another extension.",
         "parameters": [
           {"name": "request", "type": "any", "description": "The request sent by the calling script."},
           {"name": "sender", "$ref": "MessageSender" },
           {"name": "sendResponse", "type": "function", "description": "Function to call when you have a response. The argument should be any JSON-ifiable object, or undefined if there is no response." }
         ]
       }
     ]
   }
 ]