cros: Suspend media sessions with display off trigger by tablet power button

chrome/browser/chromeos/chrome_browser_main_chromeos.cc

 // Copyright (c) 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/chromeos/chrome_browser_main_chromeos.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
@@ skipping 135 matching lines @@
 #include "content/public/browser/media_capture_devices.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/main_function_params.h"
 #include "crypto/nss_util_internal.h"
 #include "crypto/scoped_nss_types.h"
 #include "dbus/object_path.h"
 #include "device/bluetooth/bluetooth_adapter_factory.h"
 #include "device/bluetooth/dbus/bluez_dbus_manager.h"
 #include "media/audio/sounds/sounds_manager.h"
+#include "media/base/media_switches.h"
 #include "net/base/network_change_notifier.h"
 #include "net/cert/nss_cert_database.h"
 #include "net/cert/nss_cert_database_chromeos.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "printing/backend/print_backend.h"
 #include "rlz/features/features.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 #include "ui/base/ime/chromeos/ime_keyboard.h"
 #include "ui/base/ime/chromeos/input_method_manager.h"
@@ skipping 741 matching lines @@
 
   // -- This used to be in ChromeBrowserMainParts::PreMainMessageLoopRun()
   // -- immediately after ChildProcess::WaitForDebugger().
 
   if (ui::ShouldDefaultToNaturalScroll()) {
     base::CommandLine::ForCurrentProcess()->AppendSwitch(
         chromeos::switches::kNaturalScrollDefault);
     system::InputDeviceSettings::Get()->SetTapToClick(true);
   }
 
+  base::CommandLine::ForCurrentProcess()->AppendSwitch(
+      ::switches::kEnableInternalMediaSession);

[Daniel Erat, 2017/05/17 01:22:25]

it seems strange to do this programmatically here. we usually pass switches from
session_manager, or perhaps better, just turn the feature on automatically
within chrome when OS_CHROMEOS is defined.

[Qiang(Joe) Xu, 2017/05/22 22:58:47]

I moved it to ChromeShellDelegate::PreInit(), is that in line with "turn the
feature on automatically within chrome when OS_CHROMEOS is defined"?

+
   ChromeBrowserMainPartsLinux::PreBrowserStart();
 }
 
 void ChromeBrowserMainPartsChromeos::PostBrowserStart() {
   if (!ash_util::IsRunningInMash()) {
     system::InputDeviceSettings::Get()->UpdateTouchDevicesStatusFromPrefs();
 
     // These are dependent on the ash::Shell singleton already having been
     // initialized. Consequently, these cannot be used when running as a mus
     // client.
@@ skipping 165 matching lines @@
 
   ChromeBrowserMainPartsLinux::PostDestroyThreads();
 
   // Destroy DeviceSettingsService after g_browser_process.
   DeviceSettingsService::Shutdown();
 
   chromeos::ShutdownCloseTracking();
 }
 
 }  //  namespace chromeos