[cros] RLZ tracking can be turned off via a flag file.

chrome/browser/google/google_util_chromeos.h

 // 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.
 
 #ifndef CHROME_BROWSER_GOOGLE_GOOGLE_UTIL_CHROMEOS_H_
 #define CHROME_BROWSER_GOOGLE_GOOGLE_UTIL_CHROMEOS_H_
 
 #include <string>
 
 #include "base/callback_forward.h"
 
 namespace google_util {
 namespace chromeos {
 
 // Returns the brand code stored in Local State that has been assigned to a
 // partner. Returns empty string if the information is not available.
 std::string GetBrand();
 
+// Sets brand for current session only, i.e. not persisted through browser
+// restart. Future calls to GetBrand() will return |brand|.
+void SetBrandForCurrentSession(const std::string& brand);

[Ilya Sherman, 2012/12/15 00:57:16]

It looks like you only ever use this method to set an empty brand code.  If I'm
understanding that correctly, it would be better to narrow the API to only
support clearing out the brand code, rather than being able to set an arbitrary
one (which I found quite surprising upon first encounter.)

[Ivan Korotkov, 2012/12/17 09:05:01]

Makes sense. I wanted to be as generic as possible but it's unlikely there'll
ever be another use for this function. Done.

+
 // Reads the brand code from a board-specific file and stores it to Local State.
 // |callback| is invoked on the calling thread after that.
 void SetBrandFromFile(const base::Closure& callback);
 
 }  // namespace chromeos
 }  // namespace google_util
 
 #endif  // CHROME_BROWSER_GOOGLE_GOOGLE_UTIL_CHROMEOS_H_