Refactor Pickle Read methods to use higher performance PickleIterator.

chrome/common/common_param_traits.h

Index: chrome/common/common_param_traits.h
diff --git a/chrome/common/common_param_traits.h b/chrome/common/common_param_traits.h
index 08a1853d9f291f551e23adc16b0e33d96215b0f0..1b9fa2333cee56f07fe57c5da45183c2df2d7be1 100644
--- a/chrome/common/common_param_traits.h
+++ b/chrome/common/common_param_traits.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 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.
 
@@ -11,6 +11,8 @@
 #include "chrome/common/content_settings.h"
 #include "ipc/ipc_param_traits.h"
 
+class PickleIterator;
+
 namespace IPC {
 
 class Message;
@@ -19,7 +21,7 @@ template <>
 struct ParamTraits<ContentSetting> {
   typedef ContentSetting param_type;
   static void Write(Message* m, const param_type& p);
-  static bool Read(const Message* m, void** iter, param_type* p);
+  static bool Read(const Message* m, PickleIterator* iter, param_type* p);
   static void Log(const param_type& p, std::string* l);
 };
 
@@ -27,7 +29,7 @@ template <>
 struct ParamTraits<ContentSettingsType> {
   typedef ContentSettingsType param_type;
   static void Write(Message* m, const param_type& p);
-  static bool Read(const Message* m, void** iter, param_type* p);
+  static bool Read(const Message* m, PickleIterator* iter, param_type* p);
   static void Log(const param_type& p, std::string* l);
 };