Make pull to refresh not perform regular reload (with cache revalidation)

content/public/browser/navigation_controller.h

Index: content/public/browser/navigation_controller.h
diff --git a/content/public/browser/navigation_controller.h b/content/public/browser/navigation_controller.h
index ac52ae13188730ea99ccac05ab66dac907d788c5..0301ab639eaae896a23030aecf4947df21473c18 100644
--- a/content/public/browser/navigation_controller.h
+++ b/content/public/browser/navigation_controller.h
@@ -357,6 +357,12 @@ class NavigationController {
   // is showing, initiates a new navigation to its URL.
   virtual void Reload(bool check_for_repost) = 0;
 
+  // Like Reload(), but for refreshing page content and may not need to
+  // validate cache content.
+  // TODO(kinuko): Update the comment once we fix the cache validation
+  // behavior.
+  virtual void ReloadToRefreshContent(bool check_for_repost) = 0;
+
   // Like Reload(), but don't use caches (aka "shift-reload").
   virtual void ReloadIgnoringCache(bool check_for_repost) = 0;