Yes let's put the checkbox back. 

Rationales for future visit:
- Support 'focused / less-distraction' use of a web site. One imaginary/but possible scenario might be a single-purpose computer with an intranet web app (e.g. a sign-up computer at a doctor's office) that should be accessed quickly & distraction-free, and that should not be easily navigated to other sites.  
- Consequences of using the same window style for the PWAs and the non-PWAs is unclear at this point. We should reassess if/when we actually encounter a negative impact in the future.

OK, assigning to Alan, when you get time.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b4a21288c503b4cf16e0a26a98687cd048bfc814

commit b4a21288c503b4cf16e0a26a98687cd048bfc814
Author: Alan Cutter <alancutter@chromium.org>
Date: Mon Nov 26 03:29:20 2018

Add "Open as window" checkbox back to Create shortcut

Before: https://bugs.chromium.org/p/chromium/issues/attachment?aid=368714&signed_aid=jxynzMCcaUtxgGB-6k_3_w==&inline=1
After: https://bugs.chromium.org/p/chromium/issues/attachment?aid=368715&signed_aid=lXnbrTuQdIjEmsYnpGspxA==&inline=1

Bug:  907339 
Change-Id: I8ed455084acc4d85f96ecbd3e124c13773bf3e25
Reviewed-on: https://chromium-review.googlesource.com/c/1349136
Commit-Queue: Alan Cutter <alancutter@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Cr-Commit-Position: refs/heads/master@{#610758}
[modify] https://crrev.com/b4a21288c503b4cf16e0a26a98687cd048bfc814/chrome/browser/extensions/bookmark_app_helper.cc
[modify] https://crrev.com/b4a21288c503b4cf16e0a26a98687cd048bfc814/chrome/browser/extensions/bookmark_app_helper_unittest.cc
[modify] https://crrev.com/b4a21288c503b4cf16e0a26a98687cd048bfc814/chrome/browser/ui/views/extensions/bookmark_app_confirmation_view.cc