So on Chrome OS & Linux we can turn on the adapter ourselves but we can't do that on macOS and Windows. I think for consistency we should just link to a help page that has instructions for each supported platform.

On ChromeOS, I would recommend having a link that points to chrome://settings/search#Bluetooth like when we click "Manage devices" in Bluetooth System Tray.

To the extent that we can, I think we should link to the place users can enable bluetooth, so +1 for chrome://settings/search#Bluetooth. If there's no way to open the control/preferences panel directly on Mac or Windows, then yes, linking to a help page is the way to go. I think we try to avoid ever doing it for the whole system from inside Chrome, although on Linux maybe there's no better way.

On non-Mac desktops, the text in the row may not be a link since it is just a base::string16:
https://cs.chromium.org/chromium/src/ui/base/models/table_model.h?type=cs&sq=package:chromium&rcl=1473160695&l=39

On Mac, it is possible since the row is an NSView.

I think this is probably what the "Get help" link can help here? We can add more help content there including how to turn on Bluetooth on different platforms.

Jun are there any plan to switch from TableView to an improved version of TableView that would give us more flexibility?

The "no results" case probably needs a different view than TableView to hold its text, like we do on Android.

For using an improved version of TableView on non-Mac desktops, we can wait and see how the material design UIs are applied to Chrome, and if a new TableView is used, we can then use it directly.

Yes, the "no results" case can have a different view, such as a link text. I can start implementing it to have the link text linking a help page. Do we need a separate help page or we can reuse the "Get help" page?

Here is the screenshot on ChromeOS that shows a text link when the Bluetooth adapter is turned off. What do you think?

Deleted: ChromeOS_turn_on_Bluetooth_link.png 65.0 KB

	ChromeOS_turn_on_Bluetooth_link.png 65.0 KB View Download

Thanks. It's a bit tight on the top and left side though. Can you bump up the padding so it's the same as when a device is listed?

Also - reminds me of a new text preference where we remove periods on single-sentence phrases. Can you remove the period here?

Thanks! New screenshot uploaded.

Deleted: ChromeOS_turn_on_Bluetooth_link_new.png 109 KB

	ChromeOS_turn_on_Bluetooth_link_new.png 109 KB View Download

I plan to add the following URL link for different platforms:

ChromeOS:
chrome://settings/search#Bluetooth
Linux:
https://help.ubuntu.com/stable/ubuntu-help/bluetooth-turn-on-off.html
Mac:
https://support.apple.com/kb/PH18971?locale=en_US
Windows:
https://support.microsoft.com/en-us/search?query=Bluetooth

Any suggestions?

Spacing in No.13 looks better, thanks.

I don't think we should link out to URLs such as these,  that may be
unstable, from the Chrome binary.

I would prefer we do so from our Bluetooth help page, which can be updated
more rapidly and includes a dedicated feedback mechanism easy to use by
most people, on the page.

So except on ChromeOS, the link can point to:
https://support.google.com/chrome?p=bluetooth
which is the same link that "Get help" points to, right?

Yes, sounds good to me to change all non-chromeOS to that link, and also please request that link to be updated with links out to each platforms' instructions.

+1 to that -- we could include platform specific URLs in the help center article

Here is the screenshot on Mac that shows a text link when the Bluetooth adapter is turned off.

Deleted: Mac_WebBluetooth_turn_on_Bluetooth_link.png 123 KB

	Mac_WebBluetooth_turn_on_Bluetooth_link.png 123 KB View Download

That LGTM

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c1bb01aa41e009f6075c5a87e945496a16976194

commit c1bb01aa41e009f6075c5a87e945496a16976194
Author: juncai <juncai@chromium.org>
Date: Thu Sep 29 22:20:19 2016

Add help link when Bluetooth adapter is off for WebBluetooth chooser

This CL adds a help link on the WebBluetooth chooser when the Bluetooth
adapter is off. This will help users get more information of how to turn
on Bluetooth.

I uploaded some screenshots on the issue page.

BUG= 644168 

Review-Url: https://codereview.chromium.org/2344133003
Cr-Commit-Position: refs/heads/master@{#421952}

[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/app/generated_resources.grd
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/chooser_controller/chooser_controller.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/chooser_controller/chooser_controller.h
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/chooser_controller/mock_chooser_controller.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/chooser_controller/mock_chooser_controller.h
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/bluetooth/bluetooth_chooser_controller_unittest.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/cocoa/extensions/chooser_dialog_cocoa_controller_unittest.mm
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/views/chooser_content_view.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/views/chooser_content_view.h
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/browser/ui/views/chooser_content_view_unittest.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/common/url_constants.cc
[modify] https://crrev.com/c1bb01aa41e009f6075c5a87e945496a16976194/chrome/common/url_constants.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4efef78587e43679bd5bdefb4eef0f208119e6b6

commit 4efef78587e43679bd5bdefb4eef0f208119e6b6
Author: juncai <juncai@chromium.org>
Date: Thu Sep 29 23:32:50 2016

Add help link when Bluetooth adapter is off for WebBluetooth chooser on Mac

This CL adds a help link on the WebBluetooth chooser when the Bluetooth
adapter is off on Mac. This will help users get more information of how
to turn on Bluetooth.

I uploaded some screenshots on the issue page.

BUG= 644168 

Review-Url: https://codereview.chromium.org/2354023003
Cr-Commit-Position: refs/heads/master@{#421980}

[modify] https://crrev.com/4efef78587e43679bd5bdefb4eef0f208119e6b6/chrome/browser/ui/cocoa/chooser_content_view_cocoa.h
[modify] https://crrev.com/4efef78587e43679bd5bdefb4eef0f208119e6b6/chrome/browser/ui/cocoa/chooser_content_view_cocoa.mm
[modify] https://crrev.com/4efef78587e43679bd5bdefb4eef0f208119e6b6/chrome/browser/ui/cocoa/extensions/chooser_dialog_cocoa_controller_unittest.mm