Change getExtensionPrinters to cr.sendWithPromise

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

Index: chrome/test/data/webui/print_preview/native_layer_stub.js
diff --git a/chrome/test/data/webui/print_preview/native_layer_stub.js b/chrome/test/data/webui/print_preview/native_layer_stub.js
index 33aca5f4d066b109394a207acd25e06d6401ba61..4e35e6b1382f1a2bf5f2575e1b41d183b5ec8a74 100644
--- a/chrome/test/data/webui/print_preview/native_layer_stub.js
+++ b/chrome/test/data/webui/print_preview/native_layer_stub.js
@@ -10,7 +10,11 @@ cr.define('print_preview', function() {
   */
   function NativeLayerStub() {
     TestBrowserProxy.call(this, [
-        'getInitialSettings', 'getPrinters', 'setupPrinter' ]);
+        'getInitialSettings',
+        'getPrinters',
+        'getExtensionPrinters',
+        'setupPrinter'
+      ]);
 
     /**
      * @private {!cr.EventTarget} The event target used for dispatching and
@@ -79,6 +83,12 @@ cr.define('print_preview', function() {
       return Promise.resolve(this.localDestinationInfos_);
     },
 
+    /** @override */
+    getExtensionPrinters: function() {
+      this.methodCalled('getExtensionPrinters');
+      return Promise.resolve(true);
+    },
+
     /** @override */
     setupPrinter: function(printerId) {
       this.methodCalled('setupPrinter', printerId);
@@ -91,7 +101,6 @@ cr.define('print_preview', function() {
     previewReadyForTest: function() {},
     startGetLocalDestinations: function() {},
     startGetPrivetDestinations: function() {},
-    startGetExtensionDestinations: function() {},
     startGetLocalDestinationCapabilities: function(destinationId) {
       if (destinationId == this.destinationToWatch_)
         this.getLocalDestinationCapabilitiesCallCount_++;