AU: fix delta generation when running out of scratch.

delta_diff_generator.h

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_DELTA_DIFF_GENERATOR_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_DELTA_DIFF_GENERATOR_H__
 
 #include <string>
 #include <vector>
 #include "base/basictypes.h"
@@ skipping 174 matching lines @@
   // if insufficient scratch is found, the file is reread and will be
   // send down (either as REPLACE or REPLACE_BZ).  Returns true on
   // success.
   static bool AssignTempBlocks(
       Graph* graph,
       const std::string& new_root,
       int data_fd,
       off_t* data_file_size,
       std::vector<Vertex::Index>* op_indexes,
       std::vector<std::vector<Vertex::Index>::size_type>* reverse_op_indexes,
-      std::vector<CutEdgeVertexes>& cuts);
+      const std::vector<CutEdgeVertexes>& cuts);
 
   // Given a new rootfs and kernel (|new_image|, |new_kernel_part|), Reads them
   // sequentially, creating a full update of chunk_size chunks.  Populates
   // |graph|, |kernel_ops|, and |final_order|, with data about the update
   // operations, and writes relevant data to |fd|, updating |data_file_size| as
   // it does. Only the first |image_size| bytes are read from |new_image|
   // assuming that this is the actual file system.
   static bool ReadFullUpdateFromDisk(
       Graph* graph,
       const std::string& new_kernel_part,
@@ skipping 18 matching lines @@
   DISALLOW_IMPLICIT_CONSTRUCTORS(DeltaDiffGenerator);
 };
 
 extern const char* const kBsdiffPath;
 extern const char* const kBspatchPath;
 extern const char* const kDeltaMagic;
 
 };  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_DELTA_DIFF_GENERATOR_H__