Revert 94073 (broke a ton of tests) - Introduce a field trial for Instant.

chrome/browser/instant/instant_field_trial.cc

-// Copyright (c) 2011 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/instant/instant_field_trial.h"
-
-#include "chrome/browser/prefs/pref_service.h"
-#include "chrome/browser/profiles/profile.h"
-#include "chrome/common/pref_names.h"
-
-// static
-InstantFieldTrial::Group InstantFieldTrial::GetGroup(Profile* profile) {
-  if (profile->IsOffTheRecord())
-    return INACTIVE;
-
-  const PrefService* prefs = profile->GetPrefs();
-  if (!prefs ||
-      prefs->GetBoolean(prefs::kInstantEnabledOnce) ||
-      prefs->IsManagedPreference(prefs::kInstantEnabled)) {
-    return INACTIVE;
-  }
-
-  const int random = prefs->GetInteger(prefs::kInstantFieldTrialRandomDraw);
-  return random < 4500 ? CONTROL1 :    // 45%
-         random < 9000 ? CONTROL2 :    // 45%
-         random < 9500 ? EXPERIMENT1   //  5%
-                       : EXPERIMENT2;  //  5%
-}
-
-// static
-bool InstantFieldTrial::IsExperimentGroup(Profile* profile) {
-  Group group = GetGroup(profile);
-  return group == EXPERIMENT1 || group == EXPERIMENT2;
-}
-
-// static
-std::string InstantFieldTrial::GetGroupName(Profile* profile) {
-  switch (GetGroup(profile)) {
-    case INACTIVE:    return "InstantInactive";
-    case CONTROL1:    return "InstantControl1";
-    case CONTROL2:    return "InstantControl2";
-    case EXPERIMENT1: return "InstantExperiment1";
-    case EXPERIMENT2: return "InstantExperiment2";
-  }
-  NOTREACHED();
-  return "InstantUnknown";
-}