Respect "do not disturb" on Linux for notifications

[metal3d]

Description

Using Brave for some "self PWA" and as browser, Brave doesn't respect the "do not disturb" state in Gnome for Linux users and displays notifications (Ads, messages from Slack, messages from Gmail...).

Google Chrome respect this state AFAIK.

Steps to Reproduce

1. Open a web page that has got notifications activated

2. Set your Gnome session in "do not disturb"
   

3. Wait for notifications...

Actual result:

Ads, and any others notifications are displayed even if I set Gnome to "do not disturb"

Expected result:

Notifications should not appear as a popup

Reproduces how often:

Always

Brave version (brave://version info)

Brave	1.9.76 Chromium: 81.0.4044.138 (Official Build) (64-bit)
Revision	8c6c7ba89cc9453625af54f11fd83179e23450fa-refs/branch-heads/4044@{#999}
OS	Linux
JavaScript	V8 8.1.307.32
Flash	(désactivée)
User Agent	Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36
Command Line	/opt/brave.com/brave/brave --profile-directory=Default --app-id=kjbdgfilnfhdoflbpgamdcdgpehopbep --enable-dom-distiller --disable-domain-reliability --no-pings --extension-content-verification=enforce_strict --extensions-install-verification=enforce --sync-url=https://no-thanks.invalid --enable-features=PasswordImport,WebUIDarkMode,PassiveMixedContentWarning,AutoupgradeMixedContent,SimplifyHttpsIndicator,MixedContentSiteSetting,DnsOverHttps --disable-features=AutofillServerCommunication,TextFragmentAnchor,AllowPopupsDuringPageUnload,NotificationTriggers,SmsReceiver,AudioServiceOutOfProcess,LookalikeUrlNavigationSuggestionsUI,VideoPlaybackQuality --flag-switches-begin --load-media-router-component-extension=1 --flag-switches-end --disable-webrtc-apm-in-audio-service --disable-sync
Executable Path	/opt/brave.com/brave/brave
Profile Path	/home/pafer/.config/BraveSoftware/Brave-Browser/Default

Other Additional Information:

• Is the issue reproducible on the latest version of Chrome? No (and older version also works as expected, Brave is the only one who has that problem)

Miscellaneous Information:

Related to #9243

[metal3d]

Additional note: This is very important. When I'm making video conferences, I don't want to let my interlocutors seeing my mail subjects when they arrive in Gmail, or message from Slack, Mattermost, and so on. Notifications should be disabled globally following the Gnome parameter.

[tmancey]

@metal3d Ads should not be shown while the browser is in full-screen mode or out of focus, i.e. another app is in focus. Can you please confirm this is working as expected for you? Thank you

[metal3d]

Sorry for the delay, it seems to work now. Thanks a lot !

[dswapnil104]

Sorry for the delay, it seems to work now. Thanks a lot !

Not sure why but the google calendar meet notifications still get through on Pop OS , Brave browser while the DnD is turned on.