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

chrome/browser/resources/pdf/pdf.js

 // Copyright 2013 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.
 
 'use strict';
 
 /**
  * @return {number} Width of a scrollbar in pixels
  */
 function getScrollbarWidth() {
@@ skipping 378 matching lines @@
       case 71: // g key.
         if (this.toolbar_ && (e.ctrlKey || e.metaKey) && e.altKey) {
           this.toolbarManager_.showToolbars();
           this.toolbar_.selectPageNumber();
         }
         return;
       case 219:  // left bracket.
         if (e.ctrlKey)
           this.rotateCounterClockwise_();
         return;
+      case 220:  // Backslash key.
+        if (e.ctrlKey) {

[raymes, 2016/08/29 03:35:09]

Do you think it might be confusing that this might result in something that is
different to what would happen by clicking the ftw/ftp button? The result of the
button actually depends on the last state of the button as opposed to the
current state of the zoom (I'd be ok if that changed though).

[Lei Zhang, 2016/08/29 05:33:54]

Probably. I'll take a closer look tomorrow.

[Lei Zhang, 2016/09/02 02:17:52]

Today is tomorrow somewhere in the world.

+          if (this.viewport_.fittingType == Viewport.FittingType.FIT_TO_PAGE) {
+            this.fitToWidth_();
+          } else {
+            this.fitToPage_();
+          }
+        }
+        return;
       case 221:  // right bracket.
         if (e.ctrlKey)
           this.rotateClockwise_();
         return;
     }
 
     // Give print preview a chance to handle the key event.
     if (!fromScriptingAPI && this.isPrintPreview_) {
       this.sendScriptingMessage_({
         type: 'sendKeyEvent',
@@ skipping 26 matching lines @@
   /**
    * @private
    * Rotate the plugin counter-clockwise.
    */
   rotateCounterClockwise_: function() {
     this.plugin_.postMessage({
       type: 'rotateCounterclockwise'
     });
   },
 
+  /**
+   * @private
+   * Set zoom to "fit to page".
+   */
   fitToPage_: function() {
     this.viewport_.fitToPage();
     this.toolbarManager_.forceHideTopToolbar();
   },
 
   /**
    * @private
+   * Set zoom to "fit to width".
+   */
+  fitToWidth_: function() {
+    this.viewport_.fitToWidth();
+    this.toolbarManager_.forceHideTopToolbar();
+  },
+
+  /**
+   * @private
    * Notify the plugin to print.
    */
   print_: function() {
     this.plugin_.postMessage({
       type: 'print'
     });
   },
 
   /**
    * @private
@@ skipping 418 matching lines @@
    * Each bookmark is an Object containing a:
    * - title
    * - page (optional)
    * - array of children (themselves bookmarks)
    * @type {Array} the top-level bookmarks of the PDF.
    */
   get bookmarks() {
     return this.bookmarks_;
   }
 };