So the reason we wouldn't want to show the interstitial here is that no reload is necessary for sound to be muted, however lgarron@ is concerned about the inconsistency with other permission changes. In particular, there are other permission changes which also don't require a refresh but we currently always show the interstitial anyway.

emilyschechter@, do you think that sound is worth an exception in this case, or should we show the interstitial anyway? 

IMO we should only show this UI if a refresh is actually required. Lucas, what permissions do we show this for where it's not required?

For regular content settings, things are not as simple as it is for the sound. For example, stuff like Javascript, images, cookies might already been used by the page so disabling that will not fully take effect until the page is reloaded. Same applies for re-enabling. For real permissions, the pages will usually try to use an API and stop if it's rejected. For example, Google Maps will unlikely re-attempt to get location if it was rejected once so reloading the page guarantees that the experience will match the intended one after the permission is re-granted. When blocking a permission, I think one of the issue is that a website that is using it might still be able to continue. This is something we could fix and therefore only show the warning when re-enabling a permission.

All of this do not apply to muting because the page isn't aware of this state and Chrome will mute/unmute immediately. Keeping the warning for consistency would only confuse/bother the users.

Notification: cached (infobar needed)
Location: immediate effect
Microphone: immediate effect
MIDI: immediate effect
Flash: don't have a good test case.

Looks like basically everything except notifications actually takes immediate effect. :-/

Would a running geolocation/camera/microphone session be suspended when the permission is changed?

Just tested microphone and camera and you if you don't refresh the site after blocking then the site can still access them.

Ah, good point. I only tested Blocked > Allow in comment #5.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/97ee2f8beaac4cf737bc93f56b0c23cd9bce7c15

commit 97ee2f8beaac4cf737bc93f56b0c23cd9bce7c15
Author: Tommy Steimel <steimel@chromium.org>
Date: Wed Nov 01 21:39:52 2017

Dont show the reload interstitial when muting a website

Bug:  776318 
Change-Id: I00307ea4f9cf44c71f21a1311e35b5b6a9ea167d
Reviewed-on: https://chromium-review.googlesource.com/731268
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Lucas Garron <lgarron@chromium.org>
Commit-Queue: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513281}
[modify] https://crrev.com/97ee2f8beaac4cf737bc93f56b0c23cd9bce7c15/chrome/browser/ui/page_info/page_info.cc
[modify] https://crrev.com/97ee2f8beaac4cf737bc93f56b0c23cd9bce7c15/chrome/browser/ui/page_info/page_info_unittest.cc