Do not update AttachmentIds after uploading attachments to sync server.

sync/syncable/mutable_entry.h

Index: sync/syncable/mutable_entry.h
diff --git a/sync/syncable/mutable_entry.h b/sync/syncable/mutable_entry.h
index 17094754b5d029c7a6d049f525ce03542fad69c7..615fe806c26f2a1806e1e1eb890d8508130775d5 100644
--- a/sync/syncable/mutable_entry.h
+++ b/sync/syncable/mutable_entry.h
@@ -62,11 +62,10 @@ class SYNC_EXPORT_PRIVATE MutableEntry : public ModelNeutralMutableEntry {
   void PutAttachmentMetadata(
       const sync_pb::AttachmentMetadata& attachment_metadata);
 
-  // Update attachment metadata, replace all records matching attachment id's
-  // unique id with updated attachment id that contains server info.
-  // Set is_in_server for corresponding records.
-  void UpdateAttachmentIdWithServerInfo(
-      const sync_pb::AttachmentIdProto& updated_attachment_id);
+  // Update attachment metadata for |attachment_id| to indicate that this
+  // attachment has been uploaded to the sync server.
+  void MarkAttachmentAsOnServer(
+      const sync_pb::AttachmentIdProto& attachment_id);
 
  private:
   // Kind of redundant. We should reduce the number of pointers