Re-enable always-on hotwording for m42 on supported hardware.

chrome/browser/search/hotword_service_factory.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_factory.h"
 
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/hotword_service.h"
@@ skipping 29 matching lines @@
 }
 
 // static
 bool HotwordServiceFactory::IsHotwordAllowed(BrowserContext* context) {
   HotwordService* hotword_service = GetForProfile(context);
   return hotword_service && hotword_service->IsHotwordAllowed();
 }
 
 // static
 bool HotwordServiceFactory::IsHotwordHardwareAvailable() {
-// Temporarily disabling hotword hardware check for M41. Will be
-// re-enabled for M42.
-#if 0
 #if defined(OS_CHROMEOS)
   if (chromeos::CrasAudioHandler::IsInitialized()) {
     chromeos::AudioDeviceList devices;
     chromeos::CrasAudioHandler::Get()->GetAudioDevices(&devices);
     for (size_t i = 0; i < devices.size(); ++i) {
       if (devices[i].type == chromeos::AUDIO_TYPE_AOKR) {
         DCHECK(devices[i].is_input);
         return true;
       }
     }
   }
 #endif
-#endif  // 0
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
   return command_line->HasSwitch(switches::kEnableExperimentalHotwordHardware);
 }
 
 // static
 int HotwordServiceFactory::GetCurrentError(BrowserContext* context) {
   HotwordService* hotword_service = GetForProfile(context);
   if (!hotword_service)
     return 0;
   return hotword_service->error_message();
@@ skipping 61 matching lines @@
                              user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   prefs->RegisterBooleanPref(prefs::kHotwordAlwaysOnNotificationSeen,
                              false,
                              user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 }
 
 KeyedService* HotwordServiceFactory::BuildServiceInstanceFor(
     BrowserContext* context) const {
   return new HotwordService(Profile::FromBrowserContext(context));
 }