Tell renderer which subframes have history items on back/forward.

content/common/navigation_params.cc

Index: content/common/navigation_params.cc
diff --git a/content/common/navigation_params.cc b/content/common/navigation_params.cc
index bbb431bf3559cbaa08440d3225a2cb4d98fc076b..fff6ef5acbc3844c768cb1572a118ac821b4a233 100644
--- a/content/common/navigation_params.cc
+++ b/content/common/navigation_params.cc
@@ -139,7 +139,6 @@ RequestNavigationParams::RequestNavigationParams()
       nav_entry_id(0),
       is_same_document_history_load(false),
       is_history_navigation_in_new_child(false),
-      has_subtree_history_items(false),
       has_committed_real_load(false),
       intended_as_new_entry(false),
       pending_history_list_offset(-1),
@@ -160,7 +159,7 @@ RequestNavigationParams::RequestNavigationParams(
     int nav_entry_id,
     bool is_same_document_history_load,
     bool is_history_navigation_in_new_child,
-    bool has_subtree_history_items,
+    std::set<std::string> subframe_unique_names,
     bool has_committed_real_load,
     bool intended_as_new_entry,
     int pending_history_list_offset,
@@ -177,7 +176,7 @@ RequestNavigationParams::RequestNavigationParams(
       nav_entry_id(nav_entry_id),
       is_same_document_history_load(is_same_document_history_load),
       is_history_navigation_in_new_child(is_history_navigation_in_new_child),
-      has_subtree_history_items(has_subtree_history_items),
+      subframe_unique_names(subframe_unique_names),
       has_committed_real_load(has_committed_real_load),
       intended_as_new_entry(intended_as_new_entry),
       pending_history_list_offset(pending_history_list_offset),