Removing this line fixes this.

https://codesearch.chromium.org/chromium/src/ui/file_manager/file_manager/foreground/js/task_controller.js?l=272&rcl=dfc69988626f677be76ad509a0dbe47d8a8ecc54

Also, applying the existing CL is another possible fix:
https://codereview.chromium.org/2828373003/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f8c224c31c133a07f58a8d922ec15aa730c06cde

commit f8c224c31c133a07f58a8d922ec15aa730c06cde
Author: tetsui <tetsui@chromium.org>
Date: Fri Jun 09 09:46:27 2017

Stop updating context menu task items when not changed.

During FileSelectionHandler.EventType.CHANGE to CHANGE_THROTTLED,
existing task items in context menu were overwritten by a temporary
item. File copy operation fires CHANGE and CHANGE_THROTTLED repeatedly,
which leads to flickering context menu during copy.
If selection is not changed, we should not clear the task items in the
context menu.

BUG= 731483 
TEST=manual
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2932803002
Cr-Commit-Position: refs/heads/master@{#478239}

[modify] https://crrev.com/f8c224c31c133a07f58a8d922ec15aa730c06cde/ui/file_manager/file_manager/foreground/js/task_controller.js

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/aa4c54cbd611f55c475eda159865c7134442f71c

commit aa4c54cbd611f55c475eda159865c7134442f71c
Author: yamaguchi <yamaguchi@chromium.org>
Date: Thu Jul 06 08:42:20 2017

Revert of Stop updating context menu task items when not changed. (patchset #2 id:20001 of https://codereview.chromium.org/2932803002/ )

Reason for revert:
We'd like to revert 2833413003 because it caused regression  crbug.com/738803 .
This is change depends on 2833413003.

Original issue's description:
> Stop updating context menu task items when not changed.
>
> During FileSelectionHandler.EventType.CHANGE to CHANGE_THROTTLED,
> existing task items in context menu were overwritten by a temporary
> item. File copy operation fires CHANGE and CHANGE_THROTTLED repeatedly,
> which leads to flickering context menu during copy.
> If selection is not changed, we should not clear the task items in the
> context menu.
>
> BUG= 731483 
> TEST=manual
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
>
> Review-Url: https://codereview.chromium.org/2932803002
> Cr-Commit-Position: refs/heads/master@{#478239}
> Committed: https://chromium.googlesource.com/chromium/src/+/f8c224c31c133a07f58a8d922ec15aa730c06cde

TBR=oka@chromium.org,fukino@chromium.org,tetsui@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG= 731483 , 738803 

Review-Url: https://codereview.chromium.org/2973003002
Cr-Commit-Position: refs/heads/master@{#484500}

[modify] https://crrev.com/aa4c54cbd611f55c475eda159865c7134442f71c/ui/file_manager/file_manager/foreground/js/task_controller.js

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/de06552d022a46e64a63a0ce601cfc463710ec17

commit de06552d022a46e64a63a0ce601cfc463710ec17
Author: Tetsui Ohkubo <tetsui@chromium.org>
Date: Tue Jul 11 05:57:13 2017

Fix double click regression and restore MTP related fixes.

MTP related fixes caused regression on the behavior when multiple files
selected are double-clicked.
These MTP related fixes were reverted in:
* https://codereview.chromium.org/2973003002/
* https://codereview.chromium.org/2966163005/

This CL restores these reverted CLs while fixes double click regression.

BUG= 462989 , 712121 , 731483 , 738803 
TEST=
unit: out/Debug/browser_tests '--gtest_filter=FileManagerJsTest.TaskController'
* Verified it fails with the original patches.
manual:
* Transfer files on MTP while selecting many source files.
* Transfer files on MTP while opening context menu.
* Double click multiple selected files.

Change-Id: If61e5f306f821d0bf096c068b01866ce1cfd38c9
Reviewed-on: https://chromium-review.googlesource.com/562912
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Commit-Queue: Tetsui Ohkubo <tetsui@chromium.org>
Cr-Commit-Position: refs/heads/master@{#485534}
[modify] https://crrev.com/de06552d022a46e64a63a0ce601cfc463710ec17/ui/file_manager/file_manager/common/js/util.js
[modify] https://crrev.com/de06552d022a46e64a63a0ce601cfc463710ec17/ui/file_manager/file_manager/foreground/js/file_tasks.js
[modify] https://crrev.com/de06552d022a46e64a63a0ce601cfc463710ec17/ui/file_manager/file_manager/foreground/js/task_controller.js
[modify] https://crrev.com/de06552d022a46e64a63a0ce601cfc463710ec17/ui/file_manager/file_manager/foreground/js/task_controller_unittest.js