Handle RenderProcessHostImpl::SetBackgrounded on Windows

chrome/browser/renderer_host/render_process_host_chrome_browsertest.cc

 // Copyright (c) 2012 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 "base/command_line.h"
 #include "base/process/process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/devtools/devtools_window.h"
 #include "chrome/browser/search/search.h"
 #include "chrome/browser/ui/browser.h"
@@ skipping 273 matching lines @@
       browser(), omnibox, NEW_FOREGROUND_TAB,
       ui_test_utils::BROWSER_TEST_WAIT_FOR_NAVIGATION);
   tab_count++;
   EXPECT_EQ(tab_count, browser()->tab_strip_model()->count());
   EXPECT_EQ(host_count, RenderProcessHostCount());
 }
 
 // We don't change process priorities on Mac or Posix because the user lacks the
 // permission to raise a process' priority even after lowering it.
 #if defined(OS_WIN) || defined(OS_LINUX)
-#if defined(OS_WIN)
-// Flaky test: crbug.com/394368
-#define MAYBE_Backgrounding DISABLED_Backgrounding
-#else
-#define MAYBE_Backgrounding Backgrounding
-#endif
-IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, MAYBE_Backgrounding) {
+IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, Backgrounding) {
   if (!base::Process::CanBackgroundProcesses()) {
     LOG(ERROR) << "Can't background processes";
     return;
   }
   base::CommandLine& parsed_command_line =
       *base::CommandLine::ForCurrentProcess();
   parsed_command_line.AppendSwitch(switches::kProcessPerTab);
 
   // Change the first tab to be the omnibox page (TYPE_WEBUI).
   GURL omnibox(chrome::kChromeUIOmniboxURL);
@@ skipping 216 matching lines @@
       chrome::NOTIFICATION_BROWSER_CLOSED,
       content::NotificationService::AllSources());
 
   // Kill the renderer process, simulating a crash. This should the ProcessDied
   // method to be called. Alternatively, RenderProcessHost::OnChannelError can
   // be called to directly force a call to ProcessDied.
   wc1->GetRenderProcessHost()->Shutdown(-1, true);
 
   observer.Wait();
 }