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

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index e8c36382cdacd55e43a5081012ba22b1d1d125e3..ce20f9849f6c0886f864c630803ce9af346f5585 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -35,6 +35,7 @@
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/sys_info.h"
+#include "base/task_scheduler/post_task.h"
 #include "base/threading/platform_thread.h"
 #include "base/time/default_tick_clock.h"
 #include "base/time/time.h"
@@ -1706,7 +1707,8 @@ int ChromeBrowserMainParts::PreMainMessageLoopRunImpl() {
   // Verify that the profile is not on a network share and if so prepare to show
   // notification to the user.
   if (NetworkProfileBubble::ShouldCheckNetworkProfile(profile_)) {
-    BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
+    base::PostTaskWithTraits(
+        FROM_HERE, base::TaskTraits().MayBlock(),
         base::Bind(&NetworkProfileBubble::CheckNetworkProfile,
                    profile_->GetPath()));
   }