Add the navigation redirect-chain to Sync sessions proto for offline analysis.

components/sessions/serialized_navigation_entry.cc

Index: components/sessions/serialized_navigation_entry.cc
diff --git a/components/sessions/serialized_navigation_entry.cc b/components/sessions/serialized_navigation_entry.cc
index 45f3cf03106807230c66c291e517dd45f957d1a6..5b5a8c49fd22ec39801ecdde1d5787d0162a08cb 100644
--- a/components/sessions/serialized_navigation_entry.cc
+++ b/components/sessions/serialized_navigation_entry.cc
@@ -57,6 +57,7 @@ SerializedNavigationEntry SerializedNavigationEntry::FromNavigationEntry(
   if (entry.GetFavicon().valid)
     navigation.favicon_url_ = entry.GetFavicon().url;
   navigation.http_status_code_ = entry.GetHttpStatusCode();
+  navigation.redirect_chain_ = entry.GetRedirectChain();
 
   return navigation;
 }
@@ -363,6 +364,7 @@ scoped_ptr<NavigationEntry> SerializedNavigationEntry::ToNavigationEntry(
   entry->SetTimestamp(timestamp_);
   entry->SetExtraData(kSearchTermsKey, search_terms_);
   entry->SetHttpStatusCode(http_status_code_);
+  entry->SetRedirectChain(redirect_chain_);
 
   // These fields should have default values.
   DCHECK_EQ(STATE_INVALID, blocked_state_);
@@ -477,6 +479,22 @@ sync_pb::TabNavigation SerializedNavigationEntry::ToSyncData() const {
     sync_data.add_content_pack_categories(*it);
   }
 
+  // Copy all redirect chain entries except the last URL (which should match
+  // the virtual_url).
+  if (redirect_chain_.size() > 1) {  // Single entry chains have no redirection.
+    size_t last_entry = redirect_chain_.size() - 1;
+    for (size_t i = 0; i < last_entry; i++) {
+      sync_pb::NavigationRedirect* navigation_redirect =
+          sync_data.add_navigation_redirect();
+      navigation_redirect->set_url(redirect_chain_[i].spec());
+    }
+    // If the last URL didn't match the virtual_url, record it separately.
+    if (sync_data.virtual_url() != redirect_chain_[last_entry].spec()) {
+      sync_data.set_last_navigation_redirect_url(
+          redirect_chain_[last_entry].spec());
+    }
+  }
+
   sync_data.set_is_restored(is_restored_);
 
   return sync_data;