Fix scrolling reset in summary

src/js/core/page.js

@@ -48,7 +48,7 @@ function setState(newState) {
     state.level        = state.page.level;
     state.filepath     = state.file.path;
     state.chapterTitle = state.page.title;
-    state.innerLanguage = state.book.language;
+    state.innerLanguage = state.book.language || '';
 
     // Absolute url to the root of the book (inner book)
     state.root = url.resolve(

src/js/theme/navigation.js

@@ -100,13 +100,13 @@ function handleNavigation(relativeUrl, push) {
 
         // Merge body
         var bodyClass = $('.book').attr('class');
-        var scrollPosition = $('.book-summary .summary').scrollTop();
+        var scrollPosition = $('.book-summary').scrollTop();
 
         $pageBody.toggleClass('with-summary', $('.book').hasClass('with-summary'));
 
         $('.book').replaceWith($pageBody);
         $('.book').attr('class', bodyClass);
-        $('.book-summary .summary').scrollTop(scrollPosition);
+        $('.book-summary').scrollTop(scrollPosition);
 
         // Scroll to hashtag position
         if (hash) {