Support for distilling prior pages in an article.

components/dom_distiller/core/page_distiller.cc

 // Copyright 2014 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.
 
 #include "components/dom_distiller/core/page_distiller.h"
 
 #include <map>
 
 #include "base/location.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 56 matching lines @@
       // The JavaScript returns an array where the first element is the title,
       // the second element is the article content HTML, and the remaining
       // elements are image URLs referenced in the HTML.
       switch (i) {
         case 0:
           page_info->title = item;
           break;
         case 1:
           page_info->html = item;
           break;
-        case 2: {
+        case 2:
           page_info->next_page_url = item;
           break;
-        }
+        case 3:
+          page_info->prev_page_url = item;
+          break;
         default:
           page_info->image_urls.push_back(item);
       }
     }
     base::MessageLoop::current()->PostTask(
         FROM_HERE,
         base::Bind(page_distiller_callback_, base::Passed(&page_info), true));
   }
 }
 
 }  // namespace dom_distiller