Cleanup: Pull some browser keep alive functions into its own file.

chrome/browser/lifetime/browser_close_manager_browsertest.cc

Index: chrome/browser/lifetime/browser_close_manager_browsertest.cc
diff --git a/chrome/browser/lifetime/browser_close_manager_browsertest.cc b/chrome/browser/lifetime/browser_close_manager_browsertest.cc
index 0eab958f094ee2fa911eb3588012cdc5f09d11cb..58c4a8590eff9dd8d158af3bafdca470ef0170cd 100644
--- a/chrome/browser/lifetime/browser_close_manager_browsertest.cc
+++ b/chrome/browser/lifetime/browser_close_manager_browsertest.cc
@@ -17,6 +17,7 @@
 #include "chrome/browser/download/download_service_factory.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/lifetime/browser_close_manager.h"
+#include "chrome/browser/lifetime/browser_keep_alive.h"
 #include "chrome/browser/net/url_request_mock_util.h"
 #include "chrome/browser/prefs/session_startup_pref.h"
 #include "chrome/browser/profiles/profile.h"
@@ -976,7 +977,7 @@ IN_PROC_BROWSER_TEST_P(BrowserCloseManagerWithBackgroundModeBrowserTest,
   {
     RepeatedNotificationObserver close_observer(
         chrome::NOTIFICATION_BROWSER_CLOSED, 1);
-    chrome::IncrementKeepAliveCount();
+    browser_lifetime::IncrementKeepAliveCount();
     chrome::CloseAllBrowsers();
     close_observer.Wait();
   }
@@ -988,7 +989,7 @@ IN_PROC_BROWSER_TEST_P(BrowserCloseManagerWithBackgroundModeBrowserTest,
   ui_test_utils::BrowserAddedObserver new_browser_observer;
   chrome::NewEmptyWindow(profile, chrome::HOST_DESKTOP_TYPE_NATIVE);
   new_browser_observer.WaitForSingleNewBrowser();
-  chrome::DecrementKeepAliveCount();
+  browser_lifetime::DecrementKeepAliveCount();
   EXPECT_FALSE(IsBackgroundModeSuspended());
   RepeatedNotificationObserver close_observer(
       chrome::NOTIFICATION_BROWSER_CLOSED, 1);
@@ -999,7 +1000,6 @@ IN_PROC_BROWSER_TEST_P(BrowserCloseManagerWithBackgroundModeBrowserTest,
   EXPECT_TRUE(browser_shutdown::IsTryingToQuit());
   EXPECT_TRUE(chrome::BrowserIterator().done());
   EXPECT_FALSE(IsBackgroundModeSuspended());
-
 }
 
 // Check that closing the last browser window individually does not affect
@@ -1023,7 +1023,7 @@ IN_PROC_BROWSER_TEST_P(BrowserCloseManagerWithBackgroundModeBrowserTest,
   RepeatedNotificationObserver close_observer(
       chrome::NOTIFICATION_BROWSER_CLOSED, 1);
   EXPECT_FALSE(IsBackgroundModeSuspended());
-  chrome::IncrementKeepAliveCount();
+  browser_lifetime::IncrementKeepAliveCount();
   browser()->window()->Close();
   close_observer.Wait();
   EXPECT_FALSE(browser_shutdown::IsTryingToQuit());