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

chrome/browser/google/google_util_chromeos.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 "base/basictypes.h"
 #include "base/bind.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
+#include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "base/task_runner_util.h"
 #include "base/threading/worker_pool.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace google_util {
@@ skipping 14 matching lines @@
   TrimWhitespace(brand, TRIM_ALL, &brand);
   return brand;
 }
 
 // Sets the brand code to |brand|.
 void SetBrand(const base::Closure& callback, const std::string& brand) {
   g_browser_process->local_state()->SetString(prefs::kRLZBrand, brand);
   callback.Run();
 }
 
+base::LazyInstance<std::string> g_temporary_brand = LAZY_INSTANCE_INITIALIZER;
+
 }  // namespace
 
+void SetBrandForCurrentSession(const std::string& brand) {
+  DCHECK(
+      !content::BrowserThread::IsWellKnownThread(content::BrowserThread::UI) ||
+      content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  g_temporary_brand.Get().assign(brand);
+}
+
 std::string GetBrand() {
   DCHECK(
       !content::BrowserThread::IsWellKnownThread(content::BrowserThread::UI) ||
       content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  // Get() should not be called as it creates an instance.
+  if (!(g_temporary_brand == NULL))

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

nit: This is usually written as "if (g_temporary_brand)", or at least as "if
(g_temporary_brand != NULL)"

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

Like I said above, LazyInstance only has operator== as means for checking if
initialized or not. LazyInstance is gone now, anyway.

+    return g_temporary_brand.Get();
   DCHECK(g_browser_process->local_state());
   return g_browser_process->local_state()->GetString(prefs::kRLZBrand);
 }
 
 void SetBrandFromFile(const base::Closure& callback) {
   base::PostTaskAndReplyWithResult(
       base::WorkerPool::GetTaskRunner(false /* task_is_slow */),
       FROM_HERE,
       base::Bind(&ReadBrandFromFile),
       base::Bind(&SetBrand, callback));
 }
 
 }  // namespace chromeos
 }  // namespace google_util