Issue reproducible on M69 (10895.49.0, 69.0.3497.87 beta-channel) as well.

Issue not reproduced on M68 (10718.88.0, 68.0.3440.118 stable-channel)

Reproduced this - fukino@, slangley@ there seems to be a few Quick view bugs in the current release?

Joel - I know you've touched this area recently, can you take a look?

Thanks.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fe3509036e3e453ae6d54b81548b8085b390e8a6

commit fe3509036e3e453ae6d54b81548b8085b390e8a6
Author: Joel Hockey <joelhockey@chromium.org>
Date: Tue Sep 25 07:09:56 2018

CrOS FilesApp: quickview scroll fix

Set html { overflow: auto } for webview which loads text.
Also removed some other CSS.  Testing shows there appears to be
no need to set overflow on pre, or to set height on body.

After changes in crosreview.com/1093402, the webview is now recognized
as being part of filesapp and gets the default platform_app.css
applied.

Bug:  883117 
Change-Id: Ic2e692e1bc246abadcdb7e05b7a8a16d2021ab9f
Reviewed-on: https://chromium-review.googlesource.com/1242646
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593844}
[modify] https://crrev.com/fe3509036e3e453ae6d54b81548b8085b390e8a6/ui/file_manager/file_manager/foreground/elements/files_safe_text_webview_content.css

Screenshots showing text display without and with scrolling.

Deleted: scroll-no-before.png 47.9 KB

	scroll-no-before.png 47.9 KB View Download

Deleted: scroll-yes-after.png 56.7 KB

	scroll-yes-after.png 56.7 KB View Download

Weifang, Stuart, should this be merged back to older releases?

We should try for 70 I think.

This bug requires manual review: M70 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: benmason@(Android), kariahda@(iOS), geohsu@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e5d803b7419f37c36542f0cc6362a6cff08c6944

commit e5d803b7419f37c36542f0cc6362a6cff08c6944
Author: Noel Gordon <noel@chromium.org>
Date: Thu Sep 27 10:41:49 2018

Add a Quick View text scrolling test

Add a test.util.async.deepExecuteScriptInWebView API, which can inject
script into the first child <webview> of a Files App (or other) window
using a CSS selector. Note the <webview> can be in shadow DOM.

Use the new API to test scrolling the QuickView <webview>. The Closure
compiler notices the executeScript() call: add new build dependency to
teach Closure about the WebView type (externs:webview_tag). Remove the
externs_list rule, externs:webview_tag provides the same files.

Test: browser_tests --gtest_filter="QuickView*openQuickViewScrollText"
Bug:  883117 
Change-Id: I494147d1f3911dd0de62a52f1e7ae5e8a726fee6
Reviewed-on: https://chromium-review.googlesource.com/1245001
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#594657}
[modify] https://crrev.com/e5d803b7419f37c36542f0cc6362a6cff08c6944/chrome/browser/chromeos/file_manager/file_manager_browsertest.cc
[add] https://crrev.com/e5d803b7419f37c36542f0cc6362a6cff08c6944/chrome/test/data/chromeos/file_manager/tall.txt
[modify] https://crrev.com/e5d803b7419f37c36542f0cc6362a6cff08c6944/ui/file_manager/file_manager/background/js/BUILD.gn
[modify] https://crrev.com/e5d803b7419f37c36542f0cc6362a6cff08c6944/ui/file_manager/file_manager/background/js/test_util_base.js
[modify] https://crrev.com/e5d803b7419f37c36542f0cc6362a6cff08c6944/ui/file_manager/integration_tests/file_manager/quick_view.js
[modify] https://crrev.com/e5d803b7419f37c36542f0cc6362a6cff08c6944/ui/file_manager/integration_tests/test_util.js

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0d60fc3d91db16efcd28a08cf442fe4e0dabbbc4

commit 0d60fc3d91db16efcd28a08cf442fe4e0dabbbc4
Author: Joel Hockey <joelhockey@chromium.org>
Date: Tue Oct 02 00:48:50 2018

CrOS FilesApp: quickview scroll fix

Set html { overflow: auto } for webview which loads text.
Also removed some other CSS.  Testing shows there appears to be
no need to set overflow on pre, or to set height on body.

After changes in crosreview.com/1093402, the webview is now recognized
as being part of filesapp and gets the default platform_app.css
applied.

Bug:  883117 
Change-Id: Ic2e692e1bc246abadcdb7e05b7a8a16d2021ab9f
Reviewed-on: https://chromium-review.googlesource.com/1242646
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#593844}(cherry picked from commit fe3509036e3e453ae6d54b81548b8085b390e8a6)
Reviewed-on: https://chromium-review.googlesource.com/1256302
Reviewed-by: Joel Hockey <joelhockey@chromium.org>
Cr-Commit-Position: refs/branch-heads/3538@{#797}
Cr-Branched-From: 79f7c91a2b2a2932cd447fa6f865cb6662fa8fa6-refs/heads/master@{#587811}
[modify] https://crrev.com/0d60fc3d91db16efcd28a08cf442fe4e0dabbbc4/ui/file_manager/file_manager/foreground/elements/files_safe_text_webview_content.css

The following revision refers to this bug: 
https://chromium.googlesource.com/chromium/src.git/+/0d60fc3d91db16efcd28a08cf442fe4e0dabbbc4

Commit: 0d60fc3d91db16efcd28a08cf442fe4e0dabbbc4
Author: joelhockey@chromium.org
Commiter: joelhockey@chromium.org
Date: 2018-10-02 00:48:50 +0000 UTC

CrOS FilesApp: quickview scroll fix

Set html { overflow: auto } for webview which loads text.
Also removed some other CSS.  Testing shows there appears to be
no need to set overflow on pre, or to set height on body.

After changes in crosreview.com/1093402, the webview is now recognized
as being part of filesapp and gets the default platform_app.css
applied.

Bug:  883117 
Change-Id: Ic2e692e1bc246abadcdb7e05b7a8a16d2021ab9f
Reviewed-on: https://chromium-review.googlesource.com/1242646
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#593844}(cherry picked from commit fe3509036e3e453ae6d54b81548b8085b390e8a6)
Reviewed-on: https://chromium-review.googlesource.com/1256302
Reviewed-by: Joel Hockey <joelhockey@chromium.org>
Cr-Commit-Position: refs/branch-heads/3538@{#797}
Cr-Branched-From: 79f7c91a2b2a2932cd447fa6f865cb6662fa8fa6-refs/heads/master@{#587811}

Filed  issue 891150  to improve here, like add html scroll test etc.