Created web::UserAgentType.

ios/web/navigation/navigation_item_impl.h

Index: ios/web/navigation/navigation_item_impl.h
diff --git a/ios/web/navigation/navigation_item_impl.h b/ios/web/navigation/navigation_item_impl.h
index 2280735b793494b12955c834f7a218c287ffc1f9..a47f1faf1dec835cf14ba0302bf50ed8da6a40a0 100644
--- a/ios/web/navigation/navigation_item_impl.h
+++ b/ios/web/navigation/navigation_item_impl.h
@@ -65,8 +65,8 @@ class NavigationItemImpl : public web::NavigationItem {
   SSLStatus& GetSSL() override;
   void SetTimestamp(base::Time timestamp) override;
   base::Time GetTimestamp() const override;
-  void SetIsOverridingUserAgent(bool is_overriding_user_agent) override;
-  bool IsOverridingUserAgent() const override;
+  void SetUserAgentType(UserAgentType type) override;
+  UserAgentType GetUserAgentType() const override;
   bool HasPostData() const override;
   NSDictionary* GetHttpRequestHeaders() const override;
   void AddHttpRequestHeaders(NSDictionary* additional_headers) override;
@@ -135,7 +135,7 @@ class NavigationItemImpl : public web::NavigationItem {
   FaviconStatus favicon_;
   SSLStatus ssl_;
   base::Time timestamp_;
-  bool is_overriding_user_agent_;
+  UserAgentType user_agent_type_;
   base::scoped_nsobject<NSMutableDictionary> http_request_headers_;
 
   base::scoped_nsobject<NSString> serialized_state_object_;