Refactor Pickle Read methods to use higher performance PickleIterator.

chrome/browser/sessions/compress_data_helper.cc

 // 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.
 
 #include "chrome/browser/sessions/compress_data_helper.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/pickle.h"
 
 #if defined(USE_SYSTEM_LIBBZ2)
@@ skipping 65 matching lines @@
   }
   if (!written) {
     // We cannot write any data. Write only the data size (0). The reading part
     // will not try to read any data after seeing the size 0.
     pickle->WriteInt(0);
   }
 }
 
 // static
 bool CompressDataHelper::ReadAndDecompressStringFromPickle(const Pickle& pickle,
-                                                           void** iter,
+                                                           PickleIterator* iter,
                                                            std::string* str) {
   // Read the size of the original data.
   int original_size = 0;
   if (!pickle.ReadLength(iter, &original_size))
     return false;
 
   if (original_size == 0) {
     // No data to decompress.
     return true;
   }
@@ skipping 35 matching lines @@
       result = BZ2_bzDecompressEnd(&stream);
       if (result == BZ_OK) {
         str->assign(original_data.get(), original_size);
       }
     } else {
       BZ2_bzDecompressEnd(&stream);
     }
   }
   return !str->empty();
 }