[Cleanup] Remove some expired omnibox field trials.

components/omnibox/browser/autocomplete_controller.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 "components/omnibox/browser/autocomplete_controller.h"
 
 #include <stddef.h>
 #include <set>
 #include <string>
 #include <utility>
@@ skipping 159 matching lines @@
 AutocompleteController::AutocompleteController(
     scoped_ptr<AutocompleteProviderClient> provider_client,
     AutocompleteControllerDelegate* delegate,
     int provider_types)
     : delegate_(delegate),
       provider_client_(std::move(provider_client)),
       history_url_provider_(NULL),
       keyword_provider_(NULL),
       search_provider_(NULL),
       zero_suggest_provider_(NULL),
-      stop_timer_duration_(OmniboxFieldTrial::StopTimerFieldTrialDuration()),
+      stop_timer_duration_(base::TimeDelta::FromMilliseconds(1500)),

[Mark P, 2016/01/14 05:31:02]

I wouldn't be surprised if we decide to experiment with this again.  Is there
any convincing reason to remove this lightweight code?

[Ilya Sherman, 2016/01/14 05:40:41]

I'd argue that it's easy enough to restore, but I don't feel strongly either
way.

       done_(true),
       in_start_(false),
       template_url_service_(provider_client_->GetTemplateURLService()) {
   provider_types &= ~OmniboxFieldTrial::GetDisabledProviderTypes();
   if (provider_types & AutocompleteProvider::TYPE_BOOKMARK)
     providers_.push_back(new BookmarkProvider(provider_client_.get()));
   if (provider_types & AutocompleteProvider::TYPE_BUILTIN)
     providers_.push_back(new BuiltinProvider(provider_client_.get()));
   if (provider_types & AutocompleteProvider::TYPE_HISTORY_QUICK)
     providers_.push_back(new HistoryQuickProvider(provider_client_.get()));
@@ skipping 461 matching lines @@
   expire_timer_.Stop();
   stop_timer_.Stop();
   done_ = true;
   if (clear_result && !result_.empty()) {
     result_.Reset();
     // NOTE: We pass in false since we're trying to only clear the popup, not
     // touch the edit... this is all a mess and should be cleaned up :(
     NotifyChanged(false);
   }
 }