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* Use AsWeakPtr instead of base::Unretained in the WizardController
* Check chrome::IsAttemptingShutdown together with
browser_shutdown::IsTryingToQuit. IsAttemptingShutdown covers call to
chrome::AttemptUserExit() which is common in the Chrome OS login/policy
code.

Bug: 1132397
Change-Id: I6c0e28138918a998c94f82f5c9e7736df92e5ced
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2450051Reviewed-by: Thomas Tellier <tellier@google.com>
Commit-Queue: Roman Sorokin [CET] <rsorokin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813764}