sync: Implement per-type commit interface

sync/engine/get_commit_ids.h

Index: sync/engine/get_commit_ids.h
diff --git a/sync/engine/get_commit_ids.h b/sync/engine/get_commit_ids.h
index 557853f36dff36340e34c9b17dfdde37c29c3ac0..358c132bed0f519c30e8ecae4b3b64cc29a3457f 100644
--- a/sync/engine/get_commit_ids.h
+++ b/sync/engine/get_commit_ids.h
@@ -15,10 +15,6 @@ using std::vector;
 
 namespace syncer {
 
-namespace sessions {
-class OrderedCommitSet;
-}
-
 namespace syncable {
 class BaseTransaction;
 }
@@ -42,15 +38,6 @@ SYNC_EXPORT_PRIVATE void GetCommitIdsForType(
     size_t max_entries,
     std::vector<int64>* out);
 
-// Fills the specified |ordered_commit_set| with up to |commit_batch_size|
-// metahandles that belong to the set of types |requested_types| and are ready
-// for commit.  The list will be in a valid commit ordering.
-SYNC_EXPORT_PRIVATE void GetCommitIds(
-    syncable::BaseTransaction* trans,
-    ModelTypeSet requested_types,
-    size_t commit_batch_size,
-    sessions::OrderedCommitSet* ordered_commit_set);
-
 }  // namespace syncer
 
 #endif  // SYNC_ENGINE_GET_COMMIT_IDS_H_