Simplify the mapping of group policies to preferences

[bsclifton]

Test plan

See the support doc and the Chromium doc for more info on enabling policies.

Testing BraveP3AEnabled and BraveStatsPingEnabled

Configure a MITM proxy for these tests.

Disable the BraveP3AEnabled policy (set to 0), keep the BraveStatsPingEnabled policy unset and start the browser. Wait a few minutes. Ensure a request was sent to usage-ping.bsg.brave.com but NOT collector.bsg.brave.com and star-randsrv.bsg.brave.com. Ensure that the Allow privacy-preserving product analytics (P3A) setting is hidden in the settings UI (brave://settings/privacy), but also ensure that the Automatically send daily usage ping to Brave setting is shown.

Test the opposite configuration (BraveP3AEnabled policy unset, BraveStatsPingEnabled disabled (set to 0)). If desired, test other policy combinations.

Testing BraveWebDiscoveryEnabled

Configure a MITM proxy for these tests.

Unset the policy (BraveWebDiscoveryEnabled), start the browser with a fresh profile, enable Web Discovery. Make some Google queries, visit some web pages, wait five minutes. Ensure a request was sent to collector.wdp.brave.com or patterns.wdp.brave.com.

Disable the BraveWebDiscoveryEnabled policy (set to 0). Start the browser with the same profile. Make some Google queries, visit some web pages, wait five minutes. Ensure a request was NOT sent to the hosts above. Ensure that the Web Discovery Project setting is not shown in the settings UI (brave://settings/search).

Test again with the BraveWebDiscoveryNative feature enabled and a fresh profile.

Description

We have Brave-specific group policies which folks can set. A full list can be seen at https://support.brave.app/hc/en-us/articles/360039248271-Group-Policy

Some of these end up having two preferences.

Policies

• BraveSpeedreaderDisabled.
  • This maps to a new preference we created speedreader::kSpeedreaderDisabledByPolicy in //brave/components/speedreader/speedreader_pref_names.h We could instead use speedreader::kSpeedreaderPrefEnabled.
  • Originally added with Add Speedreader admin policy brave-core#30017.
• BraveWaybackMachineDisabled
  • This maps to a new preference we created kBraveWaybackMachineDisabledByPolicy in //brave/components/brave_wayback_machine/pref_names.h. We could instead use kBraveWaybackMachineEnabled.
  • Originally added with Way back machine admin policy brave-core#30020.
• BraveP3ADisabled
  • This maps to a new preference we created p3a::kP3ADisabledByPolicy in //brave/components/p3a/pref_names.h. This could instead use p3a::kP3AEnabled.
  • Originally added with Add admin policies for disabling P3A and usage ping #47578 and fixed with Remove P3A disabled by policy pref, rename policy brave-core#30515.
  • The new policy name is BraveP3AEnabled.
• BraveStatsPingDisabled
  • This maps to a new preference we created kStatsReportingDisabledByPolicy in //brave/components/constants/pref_names.h. We could instead use kStatsReportingEnabled.
  • Originally added with Add admin policies for disabling P3A and usage ping #47578 and fixed with Remove stats usage ping disabled by policy pref, rename policy brave-core#30514.
  • The new policy name is BraveStatsPingEnabled.
• BraveWebDiscoveryDisabled
  • This maps to a new preference we created kWebDiscoveryDisabledByPolicy in //brave/components/constants/pref_names.h. We could instead use kWebDiscoveryEnabled.
  • Originally added with Add admin policy for Web Discovery brave-core#30023 and fixed with Remove Web Discovery disabled by policy pref, rename policy brave-core#30516.
  • The new policy name is BraveWebDiscoveryEnabled.

Some notes

• Changes for the mapping happen in //brave/browser/policy/brave_simple_policy_map.h
• When deprecating the older DisabledByPolicy preference, we should be be careful because there are places UI is being hidden. We need to put a comparable check to hide that part of the UI when the preference is managed.
• There are also automated tests that will need updating.
• Changing some of these means inverting the value. We'll want to update the policy to be ___Enabled and then update our support page.

Important steps

Besides the changes above, we'll need to do these following steps

• Update the support page with the new values
• Uplift fixes to 1.82.x. That is where the existing group policies are currently.

[bridiver]

We need to put a comparable check to hide that part of the UI when the preference is managed.

This is what prefs()->IsManagedPreference and pref->IsManaged is for
IsDefaultValue() and HasUserSetting() can also be useful. HasUserSetting() returns true even if a higher priority source (like managed prefs) is overriding it

[bridiver]

interestingly there is also

// Returns the value recommended by the admin, if any.
    const base::Value* GetRecommendedValue() const;

but not sure where that value even comes from?

[bsclifton]

@bsclifton that comes from the policy itself - it gets set in the policy YAML when someone adds a new one

[bridiver]

@bsclifton that comes from the policy itself - it gets set in the policy YAML when someone adds a new one

so the policy can override the setting or just provide a recommended setting?

[bsclifton]

@bridiver it's something the UI will recommend if a person is using the Windows group policy editor

I don't think we're setting it; you can inspect our policies here (inside BraveSoftware folder)
https://github.com/brave/brave-core/tree/master/components/policy/resources/templates/policy_definitions

Here's the documentation upstream:
https://source.chromium.org/chromium/chromium/src/+/main:components/policy/resources/new_policy_templates/policy.yaml;l=117-121;drc=75fc665835644d90269593f9f18be7a894f38b28