Classify navigations without page id in parallel to the existing classifier.

content/common/navigation_params.h

Index: content/common/navigation_params.h
diff --git a/content/common/navigation_params.h b/content/common/navigation_params.h
index 9b3fccf4ab78e61b656a68d5e077f0c0a1611989..5a02af6b47417161a8f6ae0c926e0d13084d9c94 100644
--- a/content/common/navigation_params.h
+++ b/content/common/navigation_params.h
@@ -140,6 +140,7 @@ struct CONTENT_EXPORT HistoryNavigationParams {
   HistoryNavigationParams();
   HistoryNavigationParams(const PageState& page_state,
                           int32 page_id,
+                          int nav_entry_id,
                           int pending_history_list_offset,
                           int current_history_list_offset,
                           int current_history_list_length,
@@ -155,6 +156,11 @@ struct CONTENT_EXPORT HistoryNavigationParams {
   // FrameHostMsg_DidCommitProvisionalLoad message.
   int32 page_id;
 
+  // This is the unique id of the NavigationEntry being navigated to. If the
+  // load succeeds, then this nav_entry_id will be reflected in the resultant
+  // FrameHostMsg_DidCommitProvisionalLoad message.
+  int nav_entry_id;
+
   // For history navigations, this is the offset in the history list of the
   // pending load. For non-history navigations, this will be ignored.
   int pending_history_list_offset;