Supporting command line argument to force field trials

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 13 matching lines @@
 
 void SetupPrefetchFieldTrial() {
   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
   if (channel == chrome::VersionInfo::CHANNEL_STABLE ||
       channel == chrome::VersionInfo::CHANNEL_BETA) {
     return;
   }
 
   const base::FieldTrial::Probability divisor = 1000;
   const base::FieldTrial::Probability prefetch_probability = 500;
-  scoped_refptr<base::FieldTrial> trial(
-      new base::FieldTrial("Prefetch", divisor,
-                           "ContentPrefetchPrefetchOff", 2012, 6, 30));
+  scoped_refptr<base::FieldTrial> trial(base::FieldTrial::CreateInstance(
+      "Prefetch", divisor, "ContentPrefetchPrefetchOff", 2012, 6, 30));
   const int kPrefetchOnGroup = trial->AppendGroup("ContentPrefetchPrefetchOn",
                                                   prefetch_probability);
   PrerenderManager::SetIsPrefetchEnabled(trial->group() == kPrefetchOnGroup);
 }
 
 void SetupPrerenderFieldTrial() {
   base::FieldTrial::Probability divisor = 1000;
 
   base::FieldTrial::Probability exp1_probability = 166;
   base::FieldTrial::Probability exp1_5min_ttl_probability = 83;
@@ skipping 14 matching lines @@
     no_use1_probability = 0;
     exp2_probability = 490;
     exp2_5min_ttl_probability = 5;
     control2_probability = 5;
     no_use2_probability = 0;
   }
   CHECK_EQ(divisor, exp1_probability + exp1_5min_ttl_probability +
            control1_probability + no_use1_probability + exp2_probability +
            exp2_5min_ttl_probability + control2_probability +
            no_use2_probability);
-  scoped_refptr<base::FieldTrial> trial(
-      new base::FieldTrial("Prerender", divisor,
-                           "ContentPrefetchPrerender1", 2012, 6, 30));
+  scoped_refptr<base::FieldTrial> trial(base::FieldTrial::CreateInstance(
+      "Prerender", divisor, "ContentPrefetchPrerender1", 2012, 6, 30));
 
   const int kExperiment1Group = trial->kDefaultGroupNumber;
   const int kExperiment15minTTLGroup =
       trial->AppendGroup("ContentPrefetchPrerenderExp5minTTL1",
                          exp1_5min_ttl_probability);
   const int kControl1Group =
       trial->AppendGroup("ContentPrefetchPrerenderControl1",
                          control1_probability);
   const int kNoUse1Group =
       trial->AppendGroup("ContentPrefetchPrerenderNoUse1",
@@ skipping 101 matching lines @@
   // Field trial to see if we're enabled.
   const base::FieldTrial::Probability kDivisor = 100;
 
   base::FieldTrial::Probability kDisabledProbability = 10;
   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
   if (channel == chrome::VersionInfo::CHANNEL_STABLE ||
       channel == chrome::VersionInfo::CHANNEL_BETA) {
     kDisabledProbability = 1;
   }
   scoped_refptr<base::FieldTrial> omnibox_prerender_trial(
-      new base::FieldTrial(kOmniboxTrialName, kDivisor,
-                           "OmniboxPrerenderEnabled", 2012, 8, 30));
+      base::FieldTrial::CreateInstance(
+          kOmniboxTrialName, kDivisor, "OmniboxPrerenderEnabled", 2012, 8, 30));
   omnibox_prerender_trial->AppendGroup("OmniboxPrerenderDisabled",
                                        kDisabledProbability);
 
   // Field trial to set weighting of hits.
   const base::FieldTrial::Probability kFourProbability = 33;
   const base::FieldTrial::Probability kEightProbability = 33;
 
   scoped_refptr<base::FieldTrial> weighting_trial(
-      new base::FieldTrial("OmniboxPrerenderHitWeightingTrial", kDivisor,
-                           "OmniboxPrerenderWeight1.0", 2012, 8, 30));
+      base::FieldTrial::CreateInstance("OmniboxPrerenderHitWeightingTrial",
+                                       kDivisor, "OmniboxPrerenderWeight1.0",
+                                       2012, 8, 30));
   const int kOmniboxWeightFourGroup =
       weighting_trial->AppendGroup("OmniboxPrerenderWeight4.0",
                                    kFourProbability);
   const int kOmniboxWeightEightGroup =
       weighting_trial->AppendGroup("OmniboxPrerenderWeight8.0",
                                    kEightProbability);
   const int group = weighting_trial->group();
   if (group == kOmniboxWeightFourGroup)
     NetworkActionPredictor::set_hit_weight(4.0);
   else if (group == kOmniboxWeightEightGroup)
@@ skipping 22 matching lines @@
 
     DCHECK(switch_value == switches::kPrerenderFromOmniboxSwitchValueAuto);
   }
 
   const int group = base::FieldTrialList::FindValue(kOmniboxTrialName);
   return group == base::FieldTrial::kNotFinalized ||
          group == base::FieldTrial::kDefaultGroupNumber;
 }
 
 }  // namespace prerender