OOPIF: Support session restore by combining/splitting frame states.

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 d4f88dc6c9951d895a980d8db6e985493b340967..81d46088c3d34ceb522cd3954c5c65de8d65f9a7 100644
--- a/content/common/navigation_params.h
+++ b/content/common/navigation_params.h
@@ -11,6 +11,7 @@
 #include "base/time/time.h"
 #include "content/common/content_export.h"
 #include "content/common/frame_message_enums.h"
+#include "content/common/page_state_serialization.h"
 #include "content/public/common/page_state.h"
 #include "content/public/common/referrer.h"
 #include "content/public/common/request_context_type.h"
@@ -216,6 +217,7 @@ struct CONTENT_EXPORT RequestNavigationParams {
                           bool can_load_local_resources,
                           base::Time request_time,
                           const PageState& page_state,
+                          const ExplodedFrameState& frame_state,
                           int32 page_id,
                           int nav_entry_id,
                           bool is_same_document_history_load,
@@ -244,8 +246,13 @@ struct CONTENT_EXPORT RequestNavigationParams {
   base::Time request_time;
 
   // Opaque history state (received by ViewHostMsg_UpdateState).
+  // Only used if SiteIsolationPolicy::UseSubframeNavigationEntries is false.
   PageState page_state;
 
+  // History state for this frame.
+  // Only used if SiteIsolationPolicy::UseSubframeNavigationEntries is true.
+  ExplodedFrameState frame_state;
+
   // The page_id for this navigation, or -1 if it is a new navigation.  Back,
   // Forward, and Reload navigations should have a valid page_id.  If the load
   // succeeds, then this page_id will be reflected in the resultant