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

chrome/browser/resources/pdf/pdf.js

Index: chrome/browser/resources/pdf/pdf.js
diff --git a/chrome/browser/resources/pdf/pdf.js b/chrome/browser/resources/pdf/pdf.js
index c7b172078d7778472af64c4fe851a35bca15b73e..a048c8e0cf282371e0488f970421004d63fe93b2 100644
--- a/chrome/browser/resources/pdf/pdf.js
+++ b/chrome/browser/resources/pdf/pdf.js
@@ -396,6 +396,16 @@ PDFViewer.prototype = {
         if (e.ctrlKey)
           this.rotateCounterClockwise_();
         return;
+      case 220:  // Backslash key.
+        if (e.ctrlKey) {
+          if (this.viewport_.fittingType == Viewport.FittingType.FIT_TO_PAGE) {
+            this.fitToWidth_();
+          } else {
+            this.fitToPage_();
+          }
+          this.zoomToolbar_.toggleFitButtonUIState();

[raymes, 2016/09/05 03:21:40]

Could we just call fitToggle on the zoom toolbar? I know it will be calling back
out to here, but maybe it makes the state tracking more simple? WDYT?

[Lei Zhang, 2016/09/07 00:39:09]

Done.

+        }
+        return;
       case 221:  // right bracket.
         if (e.ctrlKey)
           this.rotateClockwise_();
@@ -442,6 +452,10 @@ PDFViewer.prototype = {
     });
   },
 
+  /**
+   * @private
+   * Set zoom to "fit to page".
+   */
   fitToPage_: function() {
     this.viewport_.fitToPage();
     this.toolbarManager_.forceHideTopToolbar();
@@ -449,6 +463,15 @@ PDFViewer.prototype = {
 
   /**
    * @private
+   * Set zoom to "fit to width".
+   */
+  fitToWidth_: function() {
+    this.viewport_.fitToWidth();
+    this.toolbarManager_.forceHideTopToolbar();
+  },
+
+  /**
+   * @private
    * Notify the plugin to print.
    */
   print_: function() {