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

content/browser/frame_host/navigation_controller_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  *     (http://www.torchmobile.com/)
  *
@@ skipping 732 matching lines @@
 
       // Update the FTN ID to use below in case we found a named frame.
       frame_tree_node_id = node->frame_tree_node_id();
 
       // In --site-per-process, create an identical NavigationEntry with a
       // new FrameNavigationEntry for the target subframe.
       if (SiteIsolationPolicy::UseSubframeNavigationEntries()) {
         entry = GetLastCommittedEntry()->Clone();
         entry->SetPageID(-1);
         entry->AddOrUpdateFrameEntry(node, "", -1, -1, nullptr, params.url,
-                                     params.referrer, PageState());
+                                     params.referrer, ExplodedFrameState());
       }
     }
   }
 
   // Otherwise, create a pending entry for the main frame.
   if (!entry) {
     entry = NavigationEntryImpl::FromNavigationEntry(CreateNavigationEntry(
         params.url, params.referrer, params.transition_type,
         params.is_renderer_initiated, params.extra_headers, browser_context_));
   }
@@ skipping 129 matching lines @@
       time_smoother_.GetSmoothedTime(get_timestamp_callback_.Run());
   DVLOG(1) << "Navigation finished at (smoothed) timestamp "
            << timestamp.ToInternalValue();
 
   // We should not have a pending entry anymore.  Clear it again in case any
   // error cases above forgot to do so.
   DiscardNonCommittedEntriesInternal();
 
   // All committed entries should have nonempty content state so WebKit doesn't
   // get confused when we go back to them (see the function for details).
-  DCHECK(params.page_state.IsValid());
+  if (SiteIsolationPolicy::UseSubframeNavigationEntries())
+    DCHECK(params.frame_state.item_sequence_number);
+  else
+    DCHECK(params.page_state.IsValid());
   NavigationEntryImpl* active_entry = GetLastCommittedEntry();
   active_entry->SetTimestamp(timestamp);
   active_entry->SetHttpStatusCode(params.http_status_code);
   if (SiteIsolationPolicy::UseSubframeNavigationEntries()) {
     // Update the frame-specific PageState.
     FrameNavigationEntry* frame_entry =
         active_entry->GetFrameEntry(rfh->frame_tree_node());
     // We may not find a frame_entry in some cases; ignore the PageState if so.
     // TODO(creis): Remove the "if" once https://crbug.com/522193 is fixed.
-    if (frame_entry)
-      frame_entry->set_page_state(params.page_state);
+    if (frame_entry) {
+      frame_entry->set_frame_state(params.frame_state);
+      active_entry->UpdatePageState();
+    }
   } else {
     active_entry->SetPageState(params.page_state);
   }
   active_entry->SetRedirectChain(params.redirects);
 
   // Use histogram to track memory impact of redirect chain because it's now
   // not cleared for committed entries.
   size_t redirect_chain_size = 0;
   for (size_t i = 0; i < params.redirects.size(); ++i) {
     redirect_chain_size += params.redirects[i].spec().length();
@@ skipping 392 matching lines @@
     }
   }
 
   if (SiteIsolationPolicy::UseSubframeNavigationEntries()) {
     // This may be a "new auto" case where we add a new FrameNavigationEntry, or
     // it may be a "history auto" case where we update an existing one.
     NavigationEntryImpl* last_committed = GetLastCommittedEntry();
     last_committed->AddOrUpdateFrameEntry(
         rfh->frame_tree_node(), params.frame_unique_name,
         params.item_sequence_number, params.document_sequence_number,
-        rfh->GetSiteInstance(), params.url, params.referrer, params.page_state);
+        rfh->GetSiteInstance(), params.url, params.referrer,
+        params.frame_state);
 
     // Cross-process subframe navigations may leave a pending entry around.
     // Clear it if it's actually for the subframe.
     // TODO(creis): Don't use pending entries for subframe navigations.
     // See https://crbug.com/495161.
     if (pending_entry_ &&
         pending_entry_->frame_tree_node_id() ==
             rfh->frame_tree_node()->frame_tree_node_id()) {
       DiscardPendingEntry(false);
     }
@@ skipping 502 matching lines @@
     FrameLoadVector* different_document_loads) {
   DCHECK(pending_entry_);
   DCHECK_GE(last_committed_entry_index_, 0);
   FrameNavigationEntry* new_item = pending_entry_->GetFrameEntry(frame);
   FrameNavigationEntry* old_item =
       GetLastCommittedEntry()->GetFrameEntry(frame);
   if (!new_item)
     return;
 
   // Schedule a load in this frame if the new item isn't for the same item
-  // sequence number in the same SiteInstance.
-  // TODO(creis): Handle null SiteInstances during session restore.
+  // sequence number in the same SiteInstance. Newly restored items may not have
+  // SiteInstances yet, in which case it will be assigned on first commit.
   if (!old_item ||
       new_item->item_sequence_number() != old_item->item_sequence_number() ||
-      new_item->site_instance() != old_item->site_instance()) {
+      (new_item->site_instance() != nullptr &&
+       new_item->site_instance() != old_item->site_instance())) {
     if (old_item &&
         new_item->document_sequence_number() ==
             old_item->document_sequence_number()) {
       same_document_loads->push_back(std::make_pair(frame, new_item));
     } else {
       different_document_loads->push_back(std::make_pair(frame, new_item));
     }
     return;
   }
 
@@ skipping 166 matching lines @@
     }
   }
 }
 
 void NavigationControllerImpl::SetGetTimestampCallbackForTest(
     const base::Callback<base::Time()>& get_timestamp_callback) {
   get_timestamp_callback_ = get_timestamp_callback;
 }
 
 }  // namespace content