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 ce34bcc04bdf1d7f7bab3adab382715c5587b28f..e4d198927728685f5559ce16e9c1e872a9ae488d 100644
--- a/content/common/navigation_params.h
+++ b/content/common/navigation_params.h
@@ -170,6 +170,7 @@ struct CONTENT_EXPORT RequestNavigationParams {
                           base::Time request_time,
                           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,
@@ -207,6 +208,11 @@ struct CONTENT_EXPORT RequestNavigationParams {
   // 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;