Add ScopedKeepAlive to c/b/lifetime

chrome/browser/ui/views/auto_keep_alive.cc

 // Copyright 2014 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/ui/views/auto_keep_alive.h"
 
-#include "chrome/browser/lifetime/application_lifetime.h"
+#include "chrome/browser/lifetime/scoped_keep_alive.h"
 #include "chrome/browser/ui/host_desktop.h"
 
-AutoKeepAlive::AutoKeepAlive(gfx::NativeWindow window)
-    : keep_alive_available_(false) {
-  // In case of aura we want default to be keep alive not available for ash
-  // because ash has keep alive set and we don't want additional keep alive
-  // count.
+scoped_ptr<ScopedKeepAlive> AutoKeepAlive(gfx::NativeWindow window) {
   chrome::HostDesktopType desktop_type =

[sky, 2016/02/19 21:02:49]

desktop_type is effectively dead and in the process of being removed. If
chromeos doesn't need the keepalive you'll have to remove calls to this code
from there.

[dgn, 2016/02/22 18:01:20]

Chrome OS doesn't require it because it always increments the keepalive count
during initialization: 
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/ui/...

That's a special case that I feel should not be needed, but if it has to be
addressed that should be a separate issue. Should I file it?

In the meantime I'll just replace it by excluding ChromeOS when creating the
keepalive

       window ? chrome::GetHostDesktopTypeForNativeWindow(window)
              : chrome::GetActiveDesktop();
-  if (desktop_type != chrome::HOST_DESKTOP_TYPE_ASH) {
-    keep_alive_available_ = true;
-    chrome::IncrementKeepAliveCount();
-  }
+
+  if (desktop_type == chrome::HOST_DESKTOP_TYPE_ASH)
+    return scoped_ptr<ScopedKeepAlive>();
+
+  return make_scoped_ptr(new ScopedKeepAlive("AutoView"));
 }
-
-AutoKeepAlive::~AutoKeepAlive() {
-  if (keep_alive_available_)
-    chrome::DecrementKeepAliveCount();
-}