sync: Count nodes more efficiently

sync/internal_api/base_node.cc

Index: sync/internal_api/base_node.cc
diff --git a/sync/internal_api/base_node.cc b/sync/internal_api/base_node.cc
index 88dec8cbd36f474241e3a21fe65cf146d50dde6c..bc9443d3f7af17117ea7a01de29540ad9eed3ac8 100644
--- a/sync/internal_api/base_node.cc
+++ b/sync/internal_api/base_node.cc
@@ -216,31 +216,7 @@ int64 BaseNode::GetFirstChildId() const {
 }
 
 int BaseNode::GetTotalNodeCount() const {
-  syncable::BaseTransaction* trans = GetTransaction()->GetWrappedTrans();
-
-  int count = 1;  // Start with one to include the node itself.
-
-  std::stack<int64> stack;
-  stack.push(GetFirstChildId());
-  while (!stack.empty()) {
-    int64 handle = stack.top();
-    stack.pop();
-    if (handle == kInvalidId)
-      continue;
-    count++;
-    syncable::Entry entry(trans, syncable::GET_BY_HANDLE, handle);
-    if (!entry.good())
-      continue;
-    syncable::Id successor_id = entry.GetSuccessorId();
-    if (!successor_id.IsRoot())
-      stack.push(IdToMetahandle(trans, successor_id));
-    if (!entry.Get(syncable::IS_DIR))
-      continue;
-    syncable::Id child_id = entry.GetFirstChildId();
-    if (!child_id.IsRoot())
-      stack.push(IdToMetahandle(trans, child_id));
-  }
-  return count;
+  return GetEntry()->GetTotalNodeCount();
 }
 
 DictionaryValue* BaseNode::GetSummaryAsValue() const {