Change getExtensionPrinters to cr.sendWithPromise

chrome/test/data/webui/print_preview/native_layer_stub.js

 // Copyright 2017 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('print_preview', function() {
   /**
   * Test version of the native layer.
   * @constructor
   * @extends {TestBrowserProxy}
   */
   function NativeLayerStub() {
     TestBrowserProxy.call(this, [
-        'getInitialSettings', 'getPrinters', 'setupPrinter' ]);
+        'getInitialSettings',
+        'getPrinters',
+        'getExtensionPrinters',
+        'setupPrinter'
+      ]);
 
     /**
      * @private {!cr.EventTarget} The event target used for dispatching and
      *     receiving events.
      */
     this.eventTarget_ = new cr.EventTarget();
 
     /** @private {boolean} Whether the native layer has sent a print message. */
     this.printStarted_ = false;
 
@@ skipping 49 matching lines @@
       return Promise.resolve(this.initialSettings_);
     },
 
     /** @override */
     getPrinters: function() {
       this.methodCalled('getPrinters');
       return Promise.resolve(this.localDestinationInfos_);
     },
 
     /** @override */
+    getExtensionPrinters: function() {
+      this.methodCalled('getExtensionPrinters');
+      return Promise.resolve(true);
+    },
+
+    /** @override */
     setupPrinter: function(printerId) {
       this.methodCalled('setupPrinter', printerId);
       return this.shouldRejectPrinterSetup_ ?
           Promise.reject(this.setupPrinterResponse_) :
           Promise.resolve(this.setupPrinterResponse_);
     },
 
     /** Stubs for |print_preview.NativeLayer| methods that call C++ handlers. */
     previewReadyForTest: function() {},
     startGetLocalDestinations: function() {},
     startGetPrivetDestinations: function() {},
-    startGetExtensionDestinations: function() {},
     startGetLocalDestinationCapabilities: function(destinationId) {
       if (destinationId == this.destinationToWatch_)
         this.getLocalDestinationCapabilitiesCallCount_++;
     },
     startGetPreview: function(destination, printTicketStore, documentInfo,
                               generateDraft, requestId) {
       this.generateDraft_ = generateDraft;
     },
     startPrint: function () { this.printStarted_ = true; },
     startHideDialog: function () {},
@@ skipping 55 matching lines @@
     setSetupPrinterResponse: function(reject, response) {
       this.shouldRejectPrinterSetup_ = reject;
       this.setupPrinterResponse_ = response;
     },
   };
 
   return {
     NativeLayerStub: NativeLayerStub,
   };
 });