Migrate ChromeOS to base::MemoryPressureMonitor

chrome/browser/browser_process_platform_part_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/browser_process_platform_part_chromeos.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/time/default_tick_clock.h"
 #include "base/time/tick_clock.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/session/chrome_session_manager.h"
 #include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
 #include "chrome/browser/chromeos/memory/oom_priority_manager.h"
 #include "chrome/browser/chromeos/net/delay_network_call.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/system/automatic_reboot_manager.h"
 #include "chrome/browser/chromeos/system/device_disabling_manager.h"
 #include "chrome/browser/chromeos/system/device_disabling_manager_default_delegate.h"
 #include "chrome/browser/chromeos/system/timezone_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/common/memory_pressure_monitor_chromeos.h"
+#include "chromeos/chromeos_switches.h"
 #include "chromeos/geolocation/simple_geolocation_provider.h"
 #include "chromeos/timezone/timezone_resolver.h"
 #include "components/session_manager/core/session_manager.h"
 #include "components/user_manager/user_manager.h"
 
 BrowserProcessPlatformPart::BrowserProcessPlatformPart()
     : created_profile_helper_(false) {
 }
 
 BrowserProcessPlatformPart::~BrowserProcessPlatformPart() {
@@ skipping 53 matching lines @@
 }
 
 session_manager::SessionManager* BrowserProcessPlatformPart::SessionManager() {
   DCHECK(CalledOnValidThread());
   return session_manager_.get();
 }
 
 chromeos::OomPriorityManager*
     BrowserProcessPlatformPart::oom_priority_manager() {
   DCHECK(CalledOnValidThread());
-  if (!oom_priority_manager_.get())
+  if (!oom_priority_manager_.get()) {

[Mr4D (OOO till 08-26), 2015/03/31 21:12:17]

I suppose this is temporary?

Also - I am not sure that this will work. I remember vaguely that I moved it to
content in order to have it accessible for various target situations.
+ there were several efforts going on to separate content from chrome and vice
versa (e.g. for AppShell, etc.). This was the reason for moving the observer
into base, since that is available for all.

Looking into processes it would be even more beneficial to have them in base.

+    if (chromeos::switches::MemoryPressureHandlingEnabled()) {

[Mr4D (OOO till 08-26), 2015/03/31 21:12:17]

What was the reason for not instantiating it with the first
MemoryPressureListener creation?

+      memory_pressure_monitor_.reset(new MemoryPressureMonitorChromeOS(
+          chromeos::switches::GetMemoryPressureThresholds()));
+    }
     oom_priority_manager_.reset(new chromeos::OomPriorityManager());
+  }
   return oom_priority_manager_.get();
 }
 
 chromeos::ProfileHelper* BrowserProcessPlatformPart::profile_helper() {
   DCHECK(CalledOnValidThread());
   if (!created_profile_helper_)
     CreateProfileHelper();
   return profile_helper_.get();
 }
 
@@ skipping 36 matching lines @@
 BrowserProcessPlatformPart::CreateBrowserPolicyConnector() {
   return scoped_ptr<policy::BrowserPolicyConnector>(
       new policy::BrowserPolicyConnectorChromeOS());
 }
 
 void BrowserProcessPlatformPart::CreateProfileHelper() {
   DCHECK(!created_profile_helper_ && profile_helper_.get() == NULL);
   created_profile_helper_ = true;
   profile_helper_.reset(new chromeos::ProfileHelper());
 }