Remove Instant field trials.

This unlaunches the SILENT mode, but only for a little while. After the
rest of the refactoring is done, I'll put back the SILENT mode, along
with appropriate browser tests for all modes.

BUG=none
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10453011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@139057 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 47 insertions, 423 deletions

diff --git a/chrome/browser/instant/OWNERS b/chrome/browser/instant/OWNERS
index 90b3e80..20df7d8 100644
--- a/chrome/browser/instant/OWNERS
+++ b/chrome/browser/instant/OWNERS
@@ -1 +1,2 @@
 sky@chromium.org
+sreeram@chromium.org
diff --git a/chrome/browser/instant/instant_browsertest.cc b/chrome/browser/instant/instant_browsertest.cc
index 16104e2..960d116 100644
--- a/chrome/browser/instant/instant_browsertest.cc
+++ b/chrome/browser/instant/instant_browsertest.cc
@@ -54,8 +54,6 @@ class InstantTest : public InProcessBrowserTest {
   }
 
   void EnableInstant() {
-    CommandLine::ForCurrentProcess()->AppendSwitchASCII(
-        switches::kInstantFieldTrial, switches::kInstantFieldTrialInstant);
     InstantController::Enable(browser()->profile());
   }
 
@@ -835,180 +833,3 @@ IN_PROC_BROWSER_TEST_F(InstantTest, MAYBE(TaskManagerPrefix)) {
   string16 title = task_manager->GetResourceTitle(2);
   EXPECT_TRUE(StartsWith(title, prefix, true)) << title << " vs " << prefix;
 }
-
-// Tests the INSTANT experiment of the field trial.
-class InstantFieldTrialInstantTest : public InstantTest {
- public:
-  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
-    command_line->AppendSwitchASCII(switches::kInstantFieldTrial,
-                                    switches::kInstantFieldTrialInstant);
-  }
-};
-
-// Tests that instant is active, even without calling EnableInstant().
-IN_PROC_BROWSER_TEST_F(InstantFieldTrialInstantTest, MAYBE(ExperimentEnabled)) {
-  // Check that instant is enabled, despite not setting the preference.
-  Profile* profile = browser()->profile();
-  EXPECT_FALSE(profile->GetPrefs()->GetBoolean(prefs::kInstantEnabled));
-  EXPECT_TRUE(InstantController::IsEnabled(profile));
-
-  ASSERT_TRUE(test_server()->Start());
-  SetupInstantProvider("instant.html");
-  DetermineInstantSupport();
-  SearchAndWaitForPreviewToShow();
-
-  // Check that instant is active and showing a preview.
-  EXPECT_TRUE(preview());
-  EXPECT_TRUE(loader()->ready());
-  EXPECT_TRUE(instant()->is_displayable());
-  EXPECT_TRUE(instant()->IsCurrent());
-
-  // Check that the suggested text has been set in the omnibox.
-  EXPECT_EQ("defghi", GetSuggestion());
-  EXPECT_EQ("defghi", UTF16ToUTF8(omnibox()->GetText()));
-
-  // Press <Enter> in the omnibox, causing the preview to be committed.
-  WebContents* preview_tab = preview()->web_contents();
-  ASSERT_TRUE(PressEnter());
-
-  // The preview contents should now be the active tab contents.
-  EXPECT_FALSE(preview());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-  EXPECT_EQ(preview_tab, browser()->GetSelectedWebContents());
-}
-
-// Tests the HIDDEN experiment of the field trial.
-class InstantFieldTrialHiddenTest : public InstantTest {
- public:
-  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
-    command_line->AppendSwitchASCII(switches::kInstantFieldTrial,
-                                    switches::kInstantFieldTrialHidden);
-  }
-};
-
-// Tests that instant is active, even without calling EnableInstant().
-IN_PROC_BROWSER_TEST_F(InstantFieldTrialHiddenTest, MAYBE(ExperimentEnabled)) {
-  // Check that instant is enabled, despite not setting the preference.
-  Profile* profile = browser()->profile();
-  EXPECT_FALSE(profile->GetPrefs()->GetBoolean(prefs::kInstantEnabled));
-  EXPECT_TRUE(InstantController::IsEnabled(profile));
-
-  ASSERT_TRUE(test_server()->Start());
-  SetupInstantProvider("instant.html");
-  DetermineInstantSupport();
-
-  // Type into the omnibox, but don't press <Enter> yet.
-  omnibox()->SetUserText(ASCIIToUTF16("def"));
-  ASSERT_TRUE(WaitForMessageToBeProcessedByRenderer());
-
-  // Check that instant is active, but the preview is not showing.
-  EXPECT_TRUE(preview());
-  EXPECT_TRUE(loader()->ready());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-
-  // Check that the suggested text hasn't actually been set in the omnibox.
-  EXPECT_EQ("defghi", GetSuggestion());
-  EXPECT_EQ("def", UTF16ToUTF8(omnibox()->GetText()));
-
-  // Press <Enter> in the omnibox, causing the preview to be committed.
-  WebContents* preview_tab = preview()->web_contents();
-  ASSERT_TRUE(PressEnter());
-
-  // The preview contents should now be the active tab contents.
-  EXPECT_FALSE(preview());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-  EXPECT_EQ(preview_tab, browser()->GetSelectedWebContents());
-}
-
-// Tests the SILENT experiment of the field trial.
-class InstantFieldTrialSilentTest : public InstantTest {
- public:
-  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
-    command_line->AppendSwitchASCII(switches::kInstantFieldTrial,
-                                    switches::kInstantFieldTrialSilent);
-  }
-};
-
-// Tests that instant is active, even without calling EnableInstant().
-IN_PROC_BROWSER_TEST_F(InstantFieldTrialSilentTest, MAYBE(ExperimentEnabled)) {
-  // Check that instant is enabled, despite not setting the preference.
-  Profile* profile = browser()->profile();
-  EXPECT_FALSE(profile->GetPrefs()->GetBoolean(prefs::kInstantEnabled));
-  EXPECT_TRUE(InstantController::IsEnabled(profile));
-
-  ASSERT_TRUE(test_server()->Start());
-  SetupInstantProvider("instant.html");
-  DetermineInstantSupport();
-
-  // Type into the omnibox, but don't press <Enter> yet.
-  omnibox()->SetUserText(ASCIIToUTF16("def"));
-  ASSERT_TRUE(WaitForMessageToBeProcessedByRenderer());
-
-  // Check that instant is active, but the preview is not showing.
-  EXPECT_TRUE(preview());
-  EXPECT_FALSE(loader()->ready());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-
-  // There are no suggestions, as the loader hasn't seen the query yet.
-  EXPECT_EQ("", GetSuggestion());
-  EXPECT_EQ("def", UTF16ToUTF8(omnibox()->GetText()));
-
-  // Press <Enter> in the omnibox, causing the preview to be committed.
-  WebContents* preview_tab = preview()->web_contents();
-  ASSERT_TRUE(PressEnter());
-
-  // The preview contents should now be the active tab contents.
-  EXPECT_FALSE(preview());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-  EXPECT_EQ(preview_tab, browser()->GetSelectedWebContents());
-}
-
-// Tests the SUGGEST experiment of the field trial.
-class InstantFieldTrialSuggestTest : public InstantTest {
- public:
-  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
-    command_line->AppendSwitchASCII(switches::kInstantFieldTrial,
-                                    switches::kInstantFieldTrialSuggest);
-  }
-};
-
-// Tests that instant is active, even without calling EnableInstant().
-IN_PROC_BROWSER_TEST_F(InstantFieldTrialSuggestTest, MAYBE(ExperimentEnabled)) {
-  // Check that instant is enabled, despite not setting the preference.
-  Profile* profile = browser()->profile();
-  EXPECT_FALSE(profile->GetPrefs()->GetBoolean(prefs::kInstantEnabled));
-  EXPECT_TRUE(InstantController::IsEnabled(profile));
-
-  ASSERT_TRUE(test_server()->Start());
-  SetupInstantProvider("instant.html");
-  DetermineInstantSupport();
-
-  // Type into the omnibox, but don't press <Enter> yet.
-  omnibox()->SetUserText(ASCIIToUTF16("def"));
-  ASSERT_TRUE(WaitForMessageToBeProcessedByRenderer());
-
-  // Check that instant is active, but the preview is not showing.
-  EXPECT_TRUE(preview());
-  EXPECT_TRUE(loader()->ready());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-
-  // Check that the suggested text has actually been set in the omnibox.
-  EXPECT_EQ("defghi", GetSuggestion());
-  EXPECT_EQ("defghi", UTF16ToUTF8(omnibox()->GetText()));
-
-  // Press <Enter> in the omnibox, causing the preview to be committed.
-  WebContents* preview_tab = preview()->web_contents();
-  ASSERT_TRUE(PressEnter());
-
-  // The preview contents should now be the active tab contents.
-  EXPECT_FALSE(preview());
-  EXPECT_FALSE(instant()->is_displayable());
-  EXPECT_FALSE(instant()->IsCurrent());
-  EXPECT_EQ(preview_tab, browser()->GetSelectedWebContents());
-}
diff --git a/chrome/browser/instant/instant_controller.cc b/chrome/browser/instant/instant_controller.cc
index b6de819c..d93ed1b0 100644
--- a/chrome/browser/instant/instant_controller.cc
+++ b/chrome/browser/instant/instant_controller.cc
@@ -8,11 +8,9 @@
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
-#include "base/rand_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/autocomplete/autocomplete_match.h"
 #include "chrome/browser/instant/instant_delegate.h"
-#include "chrome/browser/instant/instant_field_trial.h"
 #include "chrome/browser/instant/instant_loader.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -36,7 +34,8 @@
 #endif
 
 InstantController::InstantController(Profile* profile,
-                                     InstantDelegate* delegate)
+                                     InstantDelegate* delegate,
+                                     Mode mode)
     : delegate_(delegate),
       template_url_service_(TemplateURLServiceFactory::GetForProfile(profile)),
       tab_contents_(NULL),
@@ -44,14 +43,11 @@ InstantController::InstantController(Profile* profile,
       is_out_of_date_(true),
       commit_on_mouse_up_(false),
       last_transition_type_(content::PAGE_TRANSITION_LINK),
-      ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
+      ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)),
+      mode_(mode) {
   DCHECK(template_url_service_);
-  PrefService* prefs = profile->GetPrefs();
-  if (prefs && prefs->GetBoolean(prefs::kInstantEnabled)) {
-    // kInstantEnabledOnce was added after Instant, set it now to make sure it
-    // is correctly set.
-    prefs->SetBoolean(prefs::kInstantEnabledOnce, true);
-  }
+  DCHECK(mode_ == INSTANT || mode_ == SUGGEST || mode_ == HIDDEN ||
+         mode_ == SILENT);
 }
 
 InstantController::~InstantController() {
@@ -65,9 +61,6 @@ void InstantController::RegisterUserPrefs(PrefService* prefs) {
   prefs->RegisterBooleanPref(prefs::kInstantEnabled,
                              false,
                              PrefService::SYNCABLE_PREF);
-  prefs->RegisterBooleanPref(prefs::kInstantEnabledOnce,
-                             false,
-                             PrefService::SYNCABLE_PREF);
 }
 
 // static
@@ -77,7 +70,8 @@ void InstantController::RecordMetrics(Profile* profile) {
 
 // static
 bool InstantController::IsEnabled(Profile* profile) {
-  return InstantFieldTrial::GetMode(profile) != InstantFieldTrial::CONTROL;
+  const PrefService* prefs = profile ? profile->GetPrefs() : 0;
+  return prefs && prefs->GetBoolean(prefs::kInstantEnabled);
 }
 
 // static
@@ -86,14 +80,9 @@ void InstantController::Enable(Profile* profile) {
   if (!service)
     return;
 
-  base::Histogram* histogram = base::LinearHistogram::FactoryGet(
-      "Instant.Preference" + InstantFieldTrial::GetModeAsString(profile),
-      1, 2, 3, base::Histogram::kUmaTargetedHistogramFlag);
-  histogram->Add(1);
-
-  service->SetBoolean(prefs::kInstantEnabledOnce, true);
   service->SetBoolean(prefs::kInstantEnabled, true);
   service->SetBoolean(prefs::kInstantConfirmDialogShown, true);
+  UMA_HISTOGRAM_ENUMERATION("Instant.Preference", 1, 2);
 }
 
 // static
@@ -102,13 +91,8 @@ void InstantController::Disable(Profile* profile) {
   if (!service || !IsEnabled(profile))
     return;
 
-  base::Histogram* histogram = base::LinearHistogram::FactoryGet(
-      "Instant.Preference" + InstantFieldTrial::GetModeAsString(profile),
-      1, 2, 3, base::Histogram::kUmaTargetedHistogramFlag);
-  histogram->Add(0);
-
-  service->SetBoolean(prefs::kInstantEnabledOnce, true);
   service->SetBoolean(prefs::kInstantEnabled, false);
+  UMA_HISTOGRAM_ENUMERATION("Instant.Preference", 0, 2);
 }
 
 // static
@@ -143,17 +127,14 @@ bool InstantController::Update(TabContentsWrapper* tab_contents,
     return false;
   }
 
-  if (!loader_.get()) {
-    loader_.reset(new InstantLoader(this, template_url->id(),
-        InstantFieldTrial::GetModeAsString(tab_contents->profile())));
-  }
+  if (!loader_.get())
+    loader_.reset(new InstantLoader(this, template_url->id(), std::string()));
 
-  // In some rare cases (involving group policy), Instant can go from the field
-  // trial to normal mode, with no intervening call to DestroyPreviewContents().
+  // In some rare cases (involving group policy), Instant can go from a hidden
+  // mode to normal mode, with no intervening call to DestroyPreviewContents().
   // This would leave the loader in a weird state, which would manifest if the
   // user pressed <Enter> without calling Update(). TODO(sreeram): Handle it.
-  if (InstantFieldTrial::GetMode(tab_contents->profile()) ==
-          InstantFieldTrial::SILENT) {
+  if (mode_ == SILENT) {
     // For the SILENT mode, we process |user_text| at commit time, which means
     // we're never really out of date.
     is_out_of_date_ = false;
@@ -179,11 +160,8 @@ void InstantController::SetOmniboxBounds(const gfx::Rect& bounds) {
   // bounds are in sync.
   omnibox_bounds_ = bounds;
 
-  if (loader_.get() && !is_out_of_date_ &&
-      InstantFieldTrial::GetMode(tab_contents_->profile()) ==
-          InstantFieldTrial::INSTANT) {
+  if (loader_.get() && !is_out_of_date_ && mode_ == INSTANT)
     loader_->SetOmniboxBounds(bounds);
-  }
 }
 
 void InstantController::DestroyPreviewContents() {
@@ -218,11 +196,8 @@ bool InstantController::PrepareForCommit() {
   if (is_out_of_date_ || !loader_.get())
     return false;
 
-  const InstantFieldTrial::Mode mode =
-      InstantFieldTrial::GetMode(tab_contents_->profile());
-
   // If we are in the visible (INSTANT) mode, return the status of the preview.
-  if (mode == InstantFieldTrial::INSTANT)
+  if (mode_ == INSTANT)
     return IsCurrent();
 
   const TemplateURL* template_url =
@@ -236,7 +211,7 @@ bool InstantController::PrepareForCommit() {
 
   // In the SUGGEST and HIDDEN modes, we must have sent an Update() by now, so
   // check if the loader failed to process it.
-  if ((mode == InstantFieldTrial::SUGGEST || mode == InstantFieldTrial::HIDDEN)
+  if ((mode_ == SUGGEST || mode_ == HIDDEN)
       && (!loader_->ready() || !loader_->http_status_ok())) {
     return false;
   }
@@ -359,10 +334,8 @@ void InstantController::OnAutocompleteGotFocus(
 
   tab_contents_ = tab_contents;
 
-  if (!loader_.get()) {
-    loader_.reset(new InstantLoader(this, template_url->id(),
-        InstantFieldTrial::GetModeAsString(tab_contents->profile())));
-  }
+  if (!loader_.get())
+    loader_.reset(new InstantLoader(this, template_url->id(), std::string()));
   loader_->MaybeLoadInstantURL(tab_contents, template_url);
 }
 
@@ -402,9 +375,7 @@ void InstantController::SetSuggestedTextFor(
   if (is_out_of_date_)
     return;
 
-  const InstantFieldTrial::Mode mode =
-      InstantFieldTrial::GetMode(tab_contents_->profile());
-  if (mode == InstantFieldTrial::INSTANT || mode == InstantFieldTrial::SUGGEST)
+  if (mode_ == INSTANT || mode_ == SUGGEST)
     delegate_->SetSuggestedText(text, behavior);
 }
 
@@ -449,24 +420,16 @@ void InstantController::InstantLoaderContentsFocused() {
 #if defined(USE_AURA)
   // On aura the omnibox only receives a focus lost if we initiate the focus
   // change. This does that.
-  if (InstantFieldTrial::GetMode(tab_contents_->profile()) ==
-          InstantFieldTrial::INSTANT) {
+  if (mode_ == INSTANT)
     delegate_->InstantPreviewFocused();
-  }
 #endif
 }
 
 void InstantController::UpdateIsDisplayable() {
-  if (!is_out_of_date_ &&
-      InstantFieldTrial::GetMode(tab_contents_->profile()) !=
-          InstantFieldTrial::INSTANT) {
-    return;
-  }
-
   bool displayable =
       (!is_out_of_date_ && loader_.get() && loader_->ready() &&
        loader_->http_status_ok());
-  if (displayable == is_displayable_)
+  if (displayable == is_displayable_ || mode_ != INSTANT)
     return;
 
   is_displayable_ = displayable;
@@ -488,15 +451,13 @@ void InstantController::UpdateLoader(const TemplateURL* template_url,
                                      bool verbatim,
                                      string16* suggested_text) {
   is_out_of_date_ = false;
-  const InstantFieldTrial::Mode mode =
-      InstantFieldTrial::GetMode(tab_contents_->profile());
-  if (mode == InstantFieldTrial::INSTANT)
+  if (mode_ == INSTANT)
     loader_->SetOmniboxBounds(omnibox_bounds_);
   loader_->Update(tab_contents_, template_url, url, transition_type, user_text,
                   verbatim, suggested_text);
   UpdateIsDisplayable();
-  // For the HIDDEN and SILENT field trials, don't send back suggestions.
-  if (mode == InstantFieldTrial::HIDDEN || mode == InstantFieldTrial::SILENT)
+  // For the HIDDEN and SILENT modes, don't send back suggestions.
+  if (mode_ == HIDDEN || mode_ == SILENT)
     suggested_text->clear();
 }
 
diff --git a/chrome/browser/instant/instant_controller.h b/chrome/browser/instant/instant_controller.h
index 97c4b06..3c461d1 100644
--- a/chrome/browser/instant/instant_controller.h
+++ b/chrome/browser/instant/instant_controller.h
@@ -48,7 +48,22 @@ class InstantController : public InstantLoaderDelegate {
   // Duration of the instant animation in which the colors change.
   static const int kAutoCommitFadeInTimeMS = 300;
 
-  InstantController(Profile* profile, InstantDelegate* delegate);
+  // InstantController may operate in one of these modes:
+  //   INSTANT: The default search engine is preloaded when the omnibox gets
+  //       focus. Queries are issued as the user types. Predicted queries are
+  //       are inline autocompleted into the omnibox. Result previews are shown.
+  //   SUGGEST: Same as INSTANT, without visible previews.
+  //   HIDDEN: Same as SUGGEST, without the inline autocompletion.
+  //   SILENT: Same as HIDDEN, without issuing queries as the user types. The
+  //       query is sent only after the user presses <Enter>.
+  enum Mode {
+    INSTANT,
+    SUGGEST,
+    HIDDEN,
+    SILENT
+  };
+
+  InstantController(Profile* profile, InstantDelegate* delegate, Mode mode);
   virtual ~InstantController();
 
   // Registers instant related preferences.
@@ -57,7 +72,7 @@ class InstantController : public InstantLoaderDelegate {
   // Records instant metrics.
   static void RecordMetrics(Profile* profile);
 
-  // Returns true if instant is enabled.
+  // Returns true if instant is enabled in the given |profile|'s preferences.
   static bool IsEnabled(Profile* profile);
 
   // Enables instant.
@@ -264,6 +279,9 @@ class InstantController : public InstantLoaderDelegate {
   // The most recent user_text passed to |Update|.
   string16 last_user_text_;
 
+  // See the enum description above.
+  const Mode mode_;
+
   DISALLOW_COPY_AND_ASSIGN(InstantController);
 };
 
diff --git a/chrome/browser/instant/instant_field_trial.cc b/chrome/browser/instant/instant_field_trial.cc
deleted file mode 100644
index 2540c1b..0000000
--- a/chrome/browser/instant/instant_field_trial.cc
+++ /dev/null
@@ -1,121 +0,0 @@
-// 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/instant/instant_field_trial.h"
-
-#include "base/command_line.h"
-#include "base/metrics/field_trial.h"
-#include "chrome/browser/metrics/metrics_service.h"
-#include "chrome/browser/prefs/pref_service.h"
-#include "chrome/browser/profiles/profile.h"
-#include "chrome/common/chrome_switches.h"
-#include "chrome/common/metrics/experiments_helper.h"
-#include "chrome/common/metrics/variation_ids.h"
-#include "chrome/common/pref_names.h"
-
-namespace {
-
-// IDs of the field trial groups. Though they are not literally "const", they
-// are set only once, in Activate() below.
-int g_instant = 0;
-int g_suggest = 0;
-int g_hidden  = 0;
-int g_silent  = 0;
-int g_control = 0;
-
-}
-
-// static
-void InstantFieldTrial::Activate() {
-  scoped_refptr<base::FieldTrial> trial(
-      base::FieldTrialList::FactoryGetFieldTrial(
-          "Instant", 1000, "CONTROL", 2013, 7, 1, &g_control));
-
-  // Try to give the user a consistent experience, if possible.
-  if (base::FieldTrialList::IsOneTimeRandomizationEnabled())
-    trial->UseOneTimeRandomization();
-
-  // Though each group (including CONTROL) is nominally at 20%, GetMode()
-  // often returns SILENT. See below for details.
-  g_instant = trial->AppendGroup("INSTANT", 200);  // 20%
-  g_suggest = trial->AppendGroup("SUGGEST", 200);  // 20%
-  g_hidden  = trial->AppendGroup("HIDDEN",  200);  // 20%
-  g_silent  = trial->AppendGroup("SILENT",  200);  // 20%
-
-  // Mark these groups in requests to Google.
-  experiments_helper::AssociateGoogleVariationID(
-      "Instant", "CONTROL", chrome_variations::kInstantIDControl);
-  experiments_helper::AssociateGoogleVariationID(
-      "Instant", "SILENT", chrome_variations::kInstantIDSilent);
-  experiments_helper::AssociateGoogleVariationID(
-      "Instant", "HIDDEN", chrome_variations::kInstantIDHidden);
-  experiments_helper::AssociateGoogleVariationID(
-      "Instant", "SUGGEST", chrome_variations::kInstantIDSuggest);
-  experiments_helper::AssociateGoogleVariationID(
-      "Instant", "INSTANT", chrome_variations::kInstantIDInstant);
-}
-
-// static
-InstantFieldTrial::Mode InstantFieldTrial::GetMode(Profile* profile) {
-  CommandLine* command_line = CommandLine::ForCurrentProcess();
-  if (command_line->HasSwitch(switches::kInstantFieldTrial)) {
-    std::string switch_value =
-        command_line->GetSwitchValueASCII(switches::kInstantFieldTrial);
-    if (switch_value == switches::kInstantFieldTrialInstant)
-      return INSTANT;
-    if (switch_value == switches::kInstantFieldTrialSuggest)
-      return SUGGEST;
-    if (switch_value == switches::kInstantFieldTrialHidden)
-      return HIDDEN;
-    if (switch_value == switches::kInstantFieldTrialSilent)
-      return SILENT;
-    return CONTROL;
-  }
-
-  // Instant explicitly enabled in chrome://settings.
-  const PrefService* prefs = profile ? profile->GetPrefs() : NULL;
-  if (prefs && prefs->GetBoolean(prefs::kInstantEnabled))
-    return INSTANT;
-
-  const int group = base::FieldTrialList::FindValue("Instant");
-  if (group == base::FieldTrial::kNotFinalized || group == g_control)
-    return CONTROL;
-
-  // HIDDEN, SUGGEST and INSTANT need non-incognito, suggest-enabled, UMA
-  // opted-in profiles.
-  if (prefs && !profile->IsOffTheRecord() &&
-      prefs->GetBoolean(prefs::kSearchSuggestEnabled) &&
-      MetricsServiceHelper::IsMetricsReportingEnabled()) {
-    if (group == g_hidden)
-      return HIDDEN;
-    if (group == g_suggest)
-      return SUGGEST;
-
-    // INSTANT also requires no group policy override and no explicit opt-out.
-    if (!prefs->IsManagedPreference(prefs::kInstantEnabled) &&
-        !prefs->GetBoolean(prefs::kInstantEnabledOnce)) {
-      if (group == g_instant)
-        return INSTANT;
-    }
-  }
-
-  // Default is SILENT. This will be returned for most users (for example, even
-  // if a user falls into another group, but has suggest or UMA disabled).
-  return SILENT;
-}
-
-// static
-std::string InstantFieldTrial::GetModeAsString(Profile* profile) {
-  const Mode mode = GetMode(profile);
-  switch (mode) {
-    case INSTANT: return "_Instant";
-    case SUGGEST: return "_Suggest";
-    case HIDDEN:  return "_Hidden";
-    case SILENT:  return "_Silent";
-    case CONTROL: return std::string();
-  }
-
-  NOTREACHED();
-  return std::string();
-}
diff --git a/chrome/browser/instant/instant_field_trial.h b/chrome/browser/instant/instant_field_trial.h
deleted file mode 100644
index 2dca72c..0000000
--- a/chrome/browser/instant/instant_field_trial.h
+++ /dev/null
@@ -1,56 +0,0 @@
-// 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.
-
-#ifndef CHROME_BROWSER_INSTANT_INSTANT_FIELD_TRIAL_H_
-#define CHROME_BROWSER_INSTANT_INSTANT_FIELD_TRIAL_H_
-
-#include <string>
-
-#include "base/basictypes.h"
-
-class Profile;
-
-// This class manages the Instant field trial, which is in one of these modes:
-//
-// INSTANT: The default search engine is preloaded when the omnibox gets focus.
-//     Queries are issued as the user types. Predicted queries are inline
-//     autocompleted into the omnibox. Result previews are shown.
-//
-// SUGGEST: Same as INSTANT, without the previews.
-//
-// HIDDEN: Same as SUGGEST, without the inline autocompletion.
-//
-// SILENT: Same as HIDDEN, without issuing queries as the user types. The query
-//     is sent only after the user presses <Enter>.
-//
-// CONTROL: Instant is disabled.
-class InstantFieldTrial {
- public:
-  enum Mode {
-    INSTANT,
-    SUGGEST,
-    HIDDEN,
-    SILENT,
-    CONTROL
-  };
-
-  // Activate the field trial and choose a mode at random. Without this, most
-  // calls to GetMode() will return CONTROL. See GetMode() for more details.
-  // *** MUST NOT BE CALLED MORE THAN ONCE. ***
-  static void Activate();
-
-  // Return the field trial mode for this profile. This will usually be the
-  // mode selected by Activate(), but can sometimes be different, depending on
-  // the profile. See the implementation in the .cc file for specific details.
-  static Mode GetMode(Profile* profile);
-
-  // Return a string describing the mode. Can be added to histogram names, to
-  // split histograms by modes.
-  static std::string GetModeAsString(Profile* profile);
-
- private:
-  DISALLOW_IMPLICIT_CONSTRUCTORS(InstantFieldTrial);
-};
-
-#endif  // CHROME_BROWSER_INSTANT_INSTANT_FIELD_TRIAL_H_