[iOS] Refactoring web CRWSessionController user agent code.

ios/web/navigation/crw_session_controller.h

Index: ios/web/navigation/crw_session_controller.h
diff --git a/ios/web/navigation/crw_session_controller.h b/ios/web/navigation/crw_session_controller.h
index 19e8f8a9c752d3ca330abbe42ced8fc0bdb14d63..e1a17d7ea24ecd8009e2740b1bcf3394a1c199f0 100644
--- a/ios/web/navigation/crw_session_controller.h
+++ b/ios/web/navigation/crw_session_controller.h
@@ -97,9 +97,9 @@ struct Referrer;
 - (void)setBrowserState:(web::BrowserState*)browserState;
 
 // Add a new item with the given url, referrer, and navigation type, making it
-// the current item. If |url| is the same as the current item's url, this
-// does nothing. |referrer| may be nil if there isn't one. The item starts
-// out as pending, and will be lost unless |-commitPendingItem| is called.
+// the current item. If pending item is the same as current item, this does
+// nothing. |referrer| may be nil if there isn't one. The item starts out as
+// pending, and will be lost unless |-commitPendingItem| is called.

[kkhorimoto, 2017/02/15 23:02:05]

I think the original comment is less ambiguous here since it's talking directly
about the input parameters.

[liaoyuke, 2017/02/16 01:49:04]

But the implementation details is not consistent with the comments, it not only
takes url into consideration, but also page transition types. 

 - (void)addPendingItem:(const GURL&)url
               referrer:(const web::Referrer&)referrer
             transition:(ui::PageTransition)type
@@ -153,10 +153,6 @@ struct Referrer;
 - (BOOL)isSameDocumentNavigationBetweenItem:(web::NavigationItem*)firstItem
                                     andItem:(web::NavigationItem*)secondItem;
 
-// Set |useDesktopUserAgentForNextPendingItem_| to YES if there is no pending
-// entry, otherwise set |useDesktopUserAgent| in the pending entry.
-- (void)useDesktopUserAgentForNextPendingItem;
-
 // Returns the index of |item| in |items|.
 - (NSInteger)indexOfItem:(const web::NavigationItem*)item;