PDF: Add shortcut to toggle fit-to-{page,width}.

chrome/test/data/pdf/material_elements_test.js

 // Copyright 2015 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.
 
 /**
  * Standalone unit tests of the PDF Polymer elements.
  */
 var tests = [
   /**
    * Test that viewer-page-selector reacts correctly to text entry. The page
@@ skipping 161 matching lines @@
 
     // Tap 2: Fire fit-to-width, show fit-to-page.
     MockInteractions.tap(fab);
     assertEvent('fit-to-width');
     chrome.test.assertTrue(fab.icon.endsWith(fitPageIcon));
 
     // Tap 3: Fire fit-to-page again.
     MockInteractions.tap(fab);
     assertEvent('fit-to-page');
 
+    // Do the same as above, but with fitToggleFromHotKey().
+    zoomToolbar.fitToggleFromHotKey();
+    assertEvent('fit-to-width');
+    zoomToolbar.fitToggleFromHotKey();
+    assertEvent('fit-to-page');
+    zoomToolbar.fitToggleFromHotKey();
+    assertEvent('fit-to-width');
+
+    // Tap 4: Fire fit-to-page again.
+    MockInteractions.tap(fab);
+    assertEvent('fit-to-page');
+
     chrome.test.succeed();
   }
 ];
 
 importTestHelpers().then(function() {
   chrome.test.runTests(tests);
 });