[Sync] Add support for enabling session sync remotely.

chrome/browser/sync/internal_api/sync_manager.cc

Index: chrome/browser/sync/internal_api/sync_manager.cc
diff --git a/chrome/browser/sync/internal_api/sync_manager.cc b/chrome/browser/sync/internal_api/sync_manager.cc
index c0b9cb35ff7e9c075139b36b90fff849a036970b..c931eb77fc77a628283e8f14144d58b333b26a3c 100644
--- a/chrome/browser/sync/internal_api/sync_manager.cc
+++ b/chrome/browser/sync/internal_api/sync_manager.cc
@@ -1968,10 +1968,19 @@ void SyncManager::RefreshEncryption() {
 }
 
 syncable::ModelTypeSet SyncManager::GetEncryptedDataTypes() const {
-  sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
+  ReadTransaction trans(FROM_HERE, GetUserShare());
   return GetEncryptedTypes(&trans);
 }
 
+bool SyncManager::ShouldEnableSessions() const {
+  ReadTransaction trans(FROM_HERE, GetUserShare());
+  ReadNode node(&trans);
+  if (!node.InitByTagLookup(kNigoriTag)) {
+    return false;

[tim (not reviewing), 2011/08/22 15:42:08]

maybe a VLOG(SyncManager::ShouldEnableSessions can't find Nigori node.)?

[Nicolas Zea, 2011/08/22 22:50:15]

Done.

+  }
+  return node.GetNigoriSpecifics().sync_tabs();
+}
+
 bool SyncManager::HasUnsyncedItems() const {
   sync_api::ReadTransaction trans(FROM_HERE, GetUserShare());
   return (trans.GetWrappedTrans()->directory()->unsynced_entity_count() != 0);