Refactor Pickle Read methods to use higher performance PickleIterator.

ipc/ipc_message.cc

Index: ipc/ipc_message.cc
diff --git a/ipc/ipc_message.cc b/ipc/ipc_message.cc
index 703588d001403d3d384efa4f97f025925a6bd851..feec91abb7194fafb241965ba24f2e3a16cc252c 100644
--- a/ipc/ipc_message.cc
+++ b/ipc/ipc_message.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -100,7 +100,7 @@ bool Message::WriteFileDescriptor(const base::FileDescriptor& descriptor) {
   }
 }
 
-bool Message::ReadFileDescriptor(void** iter,
+bool Message::ReadFileDescriptor(PickleIterator* iter,
                                  base::FileDescriptor* descriptor) const {
   int descriptor_index;
   if (!ReadInt(iter, &descriptor_index))