Mark the network bubble task as MayBlock to prevent it from crashing the browser.

chrome/browser/ui/network_profile_bubble.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 "chrome/browser/ui/network_profile_bubble.h"
 
 #include <windows.h>
 #include <stdint.h>
 
 #include <wtsapi32.h>
@@ skipping 72 matching lines @@
   if (time_since_last_check.InDays() > kSilenceDurationDays) {
     prefs->SetInteger(prefs::kNetworkProfileWarningsLeft, kMaxWarnings);
     return !notification_shown_;
   }
   return false;
 }
 
 // static
 void NetworkProfileBubble::CheckNetworkProfile(
     const base::FilePath& profile_folder) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::FILE);
   // On Windows notify the users if their profiles are located on a network
   // share as we don't officially support this setup yet.
   // However we don't want to bother users on Cytrix setups as those have no
   // real choice and their admins must be well aware of the risks associated.
   // Also the command line flag --no-network-profile-warning can stop this
   // warning from popping up. In this case we can skip the check to make the
   // start faster.
   // Collect a lot of stats along the way to see which cases do occur in the
   // wild often enough.
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
@@ skipping 68 matching lines @@
 
 // static
 void NetworkProfileBubble::NotifyNetworkProfileDetected() {
   Browser* browser = chrome::FindLastActive();
 
   if (browser)
     ShowNotification(browser);
   else
     BrowserList::AddObserver(new BrowserListObserver());
 }