[Sync] Don't commit items with predecessors/parents in conflict.

chrome/browser/sync/sessions/session_state.h

 // Copyright (c) 2012 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.
 
 // The 'sessions' namespace comprises all the pieces of state that are
 // combined to form a SyncSession instance. In that way, it can be thought of
 // as an extension of the SyncSession type itself. Session scoping gives
 // context to things like "conflict progress", "update progress", etc, and the
 // separation this file provides allows clients to only include the parts they
 // need rather than the entire session stack.
@@ skipping 158 matching lines @@
   // Various iterators, size, and retrieval functions for conflict sets.
   IdToConflictSetMap::const_iterator IdToConflictSetBegin() const;
   IdToConflictSetMap::const_iterator IdToConflictSetEnd() const;
   IdToConflictSetMap::size_type IdToConflictSetSize() const;
   IdToConflictSetMap::const_iterator IdToConflictSetFind(
       const syncable::Id& the_id) const;
   const ConflictSet* IdToConflictSetGet(const syncable::Id& the_id);
   std::set<ConflictSet*>::const_iterator ConflictSetsBegin() const;
   std::set<ConflictSet*>::const_iterator ConflictSetsEnd() const;
   std::set<ConflictSet*>::size_type ConflictSetsSize() const;
+  bool HasSimpleConflictItem(const syncable::Id& id) const;
 
   // Various mutators for tracking commit conflicts.
   void AddConflictingItemById(const syncable::Id& the_id);
   void EraseConflictingItemById(const syncable::Id& the_id);
   int ConflictingItemsSize() const { return conflicting_item_ids_.size(); }
   std::set<syncable::Id>::const_iterator ConflictingItemsBegin() const;
   std::set<syncable::Id>::const_iterator ConflictingItemsEnd() const;
 
   // Mutators for nonblocking conflicting items (see description below).
   void AddNonblockingConflictingItemById(const syncable::Id& the_id);
@@ skipping 151 matching lines @@
   ~PerModelSafeGroupState();
 
   UpdateProgress update_progress;
   ConflictProgress conflict_progress;
 };
 
 }  // namespace sessions
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_SESSIONS_SESSION_STATE_H_