Revert 146170 - Adding a field trial to enable speculative resource prefetching learning.

chrome/browser/prerender/prerender_field_trial.cc

Index: chrome/browser/prerender/prerender_field_trial.cc
===================================================================
--- chrome/browser/prerender/prerender_field_trial.cc	(revision 146220)
+++ chrome/browser/prerender/prerender_field_trial.cc	(working copy)
@@ -23,10 +23,6 @@
 const char kOmniboxTrialName[] = "PrerenderFromOmnibox";
 int g_omnibox_trial_default_group_number = -1;
 
-const char kSpeculativePrefetchingLearningTrialName[] =
-    "SpeculativePrefetchingLearning";
-int g_speculative_prefetching_learning_default_group_number = -1;
-
 void SetupPrefetchFieldTrial() {
   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
   if (channel == chrome::VersionInfo::CHANNEL_STABLE ||
@@ -126,7 +122,6 @@
 }  // end namespace
 
 void ConfigureOmniboxPrerender();
-void ConfigureSpeculativePrefetching();
 
 void ConfigurePrefetchAndPrerender(const CommandLine& command_line) {
   enum PrerenderOption {
@@ -187,7 +182,6 @@
                             PrerenderManager::PRERENDER_MODE_MAX);
 
   ConfigureOmniboxPrerender();
-  ConfigureSpeculativePrefetching();
 }
 
 void ConfigureOmniboxPrerender() {
@@ -236,46 +230,4 @@
          group == g_omnibox_trial_default_group_number;
 }
 
-void ConfigureSpeculativePrefetching() {
-  // Field trial to see if we're enabled.
-  const base::FieldTrial::Probability kDivisor = 100;
-
-  base::FieldTrial::Probability kDisabledProbability = 99;
-  chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
-  if (channel == chrome::VersionInfo::CHANNEL_STABLE ||
-      channel == chrome::VersionInfo::CHANNEL_BETA) {
-    kDisabledProbability = 100;
-  }
-  scoped_refptr<base::FieldTrial> speculative_prefetching_learning_trial(
-      base::FieldTrialList::FactoryGetFieldTrial(
-          kSpeculativePrefetchingLearningTrialName,
-          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)
-    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);
-
-    if (switch_value == switches::kSpeculativeResourcePrefetchingLearning)
-      return true;
-  }
-
-  const int group = base::FieldTrialList::FindValue(
-      kSpeculativePrefetchingLearningTrialName);
-  return group == g_speculative_prefetching_learning_default_group_number;
-}
-
 }  // namespace prerender