Use a different algorithm with the low entropy source for field trials.

content/renderer/renderer_main.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/base_switches.h"
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
 #include "base/debug/trace_event.h"
 #include "base/hi_res_timer_manager.h"
 #include "base/i18n/rtl.h"
@@ skipping 167 matching lines @@
   HighResolutionTimerManager hi_res_timer_manager;
 
   platform.PlatformInitialize();
 
   bool no_sandbox = parsed_command_line.HasSwitch(switches::kNoSandbox);
   platform.InitSandboxTests(no_sandbox);
 
   // Initialize histogram statistics gathering system.
   base::StatisticsRecorder::Initialize();
 
-  // Initialize statistical testing infrastructure.  We set client_id to the
-  // empty string to disallow the renderer process from creating its own
-  // one-time randomized trials; they should be created in the browser process.
-  base::FieldTrialList field_trial(EmptyString());
+  // Initialize statistical testing infrastructure.  We set the entropy provider
+  // to NULL to disallow the renderer process from creating its own one-time
+  // randomized trials; they should be created in the browser process.
+  base::FieldTrialList field_trial_list(NULL);
   // Ensure any field trials in browser are reflected into renderer.
   if (parsed_command_line.HasSwitch(switches::kForceFieldTrials)) {
     std::string persistent = parsed_command_line.GetSwitchValueASCII(
         switches::kForceFieldTrials);
     bool ret = base::FieldTrialList::CreateTrialsFromString(persistent);
     DCHECK(ret);
   }
 
   // Load pepper plugins before engaging the sandbox.
   PepperPluginRegistry::GetInstance();
@@ skipping 27 matching lines @@
 #endif
       TRACE_EVENT_BEGIN_ETW("RendererMain.START_MSG_LOOP", 0, 0);
       MessageLoop::current()->Run();
       TRACE_EVENT_END_ETW("RendererMain.START_MSG_LOOP", 0, 0);
     }
   }
   platform.PlatformUninitialize();
   TRACE_EVENT_END_ETW("RendererMain", 0, "");
   return 0;
 }