mkarkada@ - To clarify the setting of the default, is the app selected at random or is it the first app which was installed?

+fukino@ - FYI.

Re#1, @fukino, @weifangsun,

The app is selected at random. It is neither the first installed app chosen nor the recently installed app.

Thank you!

Thanks for the clarification!

yamaguchi@ - Maybe we can investigate the default app setting logic when we implement crbug.com/751950 for the new text app?

Now I got how it happened.
It's currently showing the first item (except the generic handler) returned from the private API when the default is not set. This is why it looks random. (Just FYI, with current implementation, Chrome apps will appear before Android apps. The ordering depends on how the entries were retrieved from the app repository.)

The UI shows "(default)" when opening the "open by..." dialog even in the reported case, but it'd internally not having the default actually.
https://cs.chromium.org/chromium/src/ui/file_manager/file_manager/foreground/js/file_tasks.js?type=cs&q=%22if+we+haven%27t+picked+a+default+task+yet%22&sq=package:chromium&rcl=0b49eba721c71610781a80d243184dbf9a273aea&l=281

So I'd change the UX flow to show the app picker in such case.

We'll need to change some UI.

1. In the context menu, we currently have these as the first two items when there are 2 or more possible actions.
---------------------------
Open with <app name> [icon]
More actions...
---------------------------

1A. When the default app is not set but there are 2 or more apps (not including "share with X" actions),
- We'll remove the first menu item above.
- Also change the label for the 2nd item, because "More" will not make sense without the first item. << new text resource required >>
- All the files will be shown with the plain paper icon (for "other" file types) until user sets the default app for the file type, or there's thumbnail data available.

My suggestion for the new text resource is:
-------------------------
Select action...
-------------------------

1B. When there's only 1 app, we'll show only
---------------------------
Open with <app name> [icon]
---------------------------
in the context menu despite it's not explicitly set as default. (same as existing behavior)

2. In the toolbar, we'll just reuse "OPEN" button to open the app picker dialog. (No additional text resource needed.)

fukino@, will you double check on this idea?

Let me explain the M62 behavior about the default app. (Actually it's not random.)

In OPEN menu, apps are sorted as follows:
1. If a user explicitly specify the default app in "Change default..." dialog, it comes first.
2. Other apps are sorted by last-executed time (recently-used app comes first).
3. Apps which haven't executed yet are sorted alphabetically.

The first item in the menu is considered as the default, which will be executed on double-click.

My understanding about the issue as follows:
When all apps are neither explicitly specified as default nor executed at least once, the alphabetically-first app is executed by default, which looks random to the user.

If my understanding is correct, it should work that hiding the app and opening the app picker dialog on double-click when following condition are met.
1) There are at least two OPEN apps.
2) No app is specified as default by the user.
3) No app hasn't been executed.

I found that my comment #5 was based on M61 or before. Currently we already have "Open with..." menu item in addition to "More actions...".
So we won't need additional text resource which I noted in #5.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6f148d5ce774a49dc8743c31ef4278e2b9a73bfe

commit 6f148d5ce774a49dc8743c31ef4278e2b9a73bfe
Author: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Date: Wed Nov 01 04:00:48 2017

Open task picker when there are multiple apps but default is not set.

Bug:  761154 
Test: gtest_filter=FileManagerJsTest.FileTasks:GenericTask/FileManagerBrowserTest.*
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I43b04bac3a5d5683d3a8c5afba71f19ce77c8231
Reviewed-on: https://chromium-review.googlesource.com/725959
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Commit-Queue: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513069}
[modify] https://crrev.com/6f148d5ce774a49dc8743c31ef4278e2b9a73bfe/ui/file_manager/file_manager/foreground/js/file_tasks.js
[modify] https://crrev.com/6f148d5ce774a49dc8743c31ef4278e2b9a73bfe/ui/file_manager/file_manager/foreground/js/file_tasks_unittest.js
[modify] https://crrev.com/6f148d5ce774a49dc8743c31ef4278e2b9a73bfe/ui/file_manager/integration_tests/file_manager/tasks.js

This was planned for M63, but since this is P2 and this is not a regression, punting to M64.

I guess this issue seems not fixed yet.
Attaching the issue video in this link:
https://pantheon.corp.google.com/storage/browser/chromiumos-test-logs/bugfiles/cr/761154/

From the video,
1. Double click on .docx file, user was given the option to choose among the two apps.
2. But with TIFF file, it is an unsupported file type. One among the two installed apps i.e. Photos app got randomly set to default. User was not given option to choose among the apps (like how it worked with .docx file). 

Tested on on M64 dev build (10109.0.0, 64.0.3261.0).

> 2. But with TIFF file, it is an unsupported file type. One among the two installed apps i.e. Photos app got randomly set to default. 

I think the it was WAI if a TIFF file was opened by the photos app before on the user's profile before. It is rule #3 in Comment #6.
> 3) No app hasn't been executed.
 --- if any of the apps has ever been run before, use the most recent one.

I've found we need 2 more changes to do.
- It should not show the "default" app (picked by the alphabetical order) in the context menu when the conditions are met.
- It should not say "(default)" in the app picker dialog when the conditions are met.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/cd09a61e56e620c468690c6b23b11ab3855ac05a

commit cd09a61e56e620c468690c6b23b11ab3855ac05a
Author: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Date: Wed Nov 15 09:25:53 2017

Cleanup logic to choose default action and show it correctly in menus.

This change fixes UI inconsistency after the change http://crrev.com/c/725959.
- "default" app in the context menu when it actually show task picker.
- "(default)" notation in the app picker.


Bug:  761154 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I408a820780ef7c55a9a6e09fc3691ee6c88d40a4
Reviewed-on: https://chromium-review.googlesource.com/762911
Commit-Queue: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516650}
[modify] https://crrev.com/cd09a61e56e620c468690c6b23b11ab3855ac05a/ui/file_manager/file_manager/foreground/js/file_tasks.js
[modify] https://crrev.com/cd09a61e56e620c468690c6b23b11ab3855ac05a/ui/file_manager/file_manager/foreground/js/file_tasks_unittest.js
[modify] https://crrev.com/cd09a61e56e620c468690c6b23b11ab3855ac05a/ui/file_manager/file_manager/foreground/js/task_controller.js