This reverts commit 049eaa11.

Reason for revert: <INSERT REASONING HERE>

Original change's description:
> Download auto-open files to temp folder
> 
> If a user has marked a file extension to auto-open on download, we
> assume that the user only intends to use the file for one-time use.
> Therefore, these files are now downloaded to the system temp directory
> to prevent cluttering the user's download folder.
> 
> Download the file again -- the first file will be in your downloads
> folder, but the second one will be in the temp directory.
> 
> Bug: 55567
> Test: Download a file and choose to Always Open Files of This Type. 
> Change-Id: If23db247f7ed03df7c4f2492c3fefe5e37c8f8ca
> Reviewed-on: https://chromium-review.googlesource.com/602788


> Commit-Queue: David Trainor <dtrainor@chromium.org>
> Reviewed-by: David Trainor <dtrainor@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#493787}

TBR=dtrainor@chromium.org,jbudorick@chromium.org,lenny.khazan@gmail.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 55567
Change-Id: Ie1c3df69c1bf05d7291bc6373b3f9a4254a03d5f
Reviewed-on: https://chromium-review.googlesource.com/655877


Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: David Trainor <dtrainor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#500693}