[Hotword] Reverse the experimental flag so that it is on by default.

chrome/browser/search/hotword_service.cc

 // Copyright 2013 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/search/hotword_service.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/i18n/case_conversion.h"
@@ skipping 194 matching lines @@
 // static
 bool HotwordService::IsExperimentalHotwordingEnabled() {
   std::string group = base::FieldTrialList::FindFullName(
       hotword_internal::kHotwordFieldTrialName);
   if (!group.empty() &&
       group == hotword_internal::kHotwordFieldTrialExperimentalGroupName) {
     return true;
   }
 
   CommandLine* command_line = CommandLine::ForCurrentProcess();
-  return command_line->HasSwitch(switches::kEnableExperimentalHotwording);
+  return !command_line->HasSwitch(switches::kDisableExperimentalHotwording);
 }
 
 HotwordService::HotwordService(Profile* profile)
     : profile_(profile),
       extension_registry_observer_(this),
       client_(NULL),
       error_message_(0),
       reinstall_pending_(false),
       training_(false),
       weak_factory_(this) {
@@ skipping 397 matching lines @@
     return false;
 
   std::string previous_locale =
       profile_->GetPrefs()->GetString(prefs::kHotwordPreviousLanguage);
   std::string locale = GetCurrentLocale(profile_);
 
   // If it's a new locale, then the old extension should be uninstalled.
   return locale != previous_locale &&
       HotwordService::DoesHotwordSupportLanguage(profile_);
 }