Adding more histograms to ResourcePrefetchPredictor.

chrome/browser/prerender/prerender_field_trial.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 "chrome/browser/prerender/prerender_field_trial.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
@@ skipping 257 matching lines @@
           kDivisor,
           "SpeculativePrefetchingLearningEnabled",
           2012, 12, 30,
           &g_speculative_prefetching_learning_default_group_number));
   speculative_prefetching_learning_trial->AppendGroup(
       "SpeculativePrefetchingDisabled",
       kDisabledProbability);
 }
 
 bool IsSpeculativeResourcePrefetchingLearningEnabled(Profile* profile) {
-  if (!profile)
+  if (!profile || profile->IsOffTheRecord())
     return false;
 
   // Override any field trial groups if the user has set a command line flag.
   if (CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kSpeculativeResourcePrefetching)) {
     const std::string switch_value =
         CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
             switches::kSpeculativeResourcePrefetching);
 
     return switch_value == switches::kSpeculativeResourcePrefetchingLearning;
   }
 
   const int group = FieldTrialList::FindValue(
       kSpeculativePrefetchingLearningTrialName);
   return group == g_speculative_prefetching_learning_default_group_number;
 }
 
 }  // namespace prerender