Onboarding P3A opt-in checkbox does not work

[DJAndries]

Description

The P3A opt-in checkbox embedded in the new desktop onboarding UI does not correctly set the P3A preference. If the checkbox is checked, P3A is not enabled.

Steps to Reproduce

1. Start with fresh profile
2. Go through onboarding and ensure P3A checkbox is checked.
3. Examine P3A preference in the browser settings.

Actual result:

P3A is disabled.

Expected result:

P3A should be enabled.

Reproduces how often:

Easily

Desktop Brave version:

1.47 and up

cc @nullhook

[GeetaSarvadnya]

Good catch @DJAndries

Reproduced on Windows 10 x64 - 1.47.115

Brave | 1.47.115 Chromium: 108.0.5359.94 (Official Build) beta (64-bit)
-- | --
Revision | 713576b895246504ccc6b92c2fb8ce2d60194074-refs/branch-heads/5359_71@{#3}
OS | Windows 10 Version 21H2 (Build 19044.2251)

[kjozwiak]

The above requires 1.47.131 or higher for 1.47.x verification 👍

[GeetaSarvadnya]

Verification PASSED on

Brave | 1.47.149 Chromium: 109.0.5414.46 (Official Build) beta (64-bit)
-- | --
Revision | 6e36b77363ef3febbe792af680fa1367993ddcf0-refs/branch-heads/5414@{#709}
OS | Windows 10 Version 21H2 (Build 19044.2364)

Clean profile

• Ensured that the P3A checkbox in onboarding flow is checked by default
• Ensured that the P3A checkbox is checked by default in brave://settings/privacy
• Ensured that disable P3A checkbox in brave://welcome onboarding flow disables the P3A switch in brave://settings/privacy
• Ensured that the restart browser retain the switch state in brave://settings/privacy

P3A checked in Onboarding	brave://settings/privacy

P3A unchecked in Onboarding	brave://settings/privacy

Upgrade profile

• Install 1.46.x beta build and disable the P3A switch via brave://settings/privacy and upgrade the profile to 1.47.x beta build and ensure that the P3A settings is disabled via brave://settings/privacy and ensured user can enable the switch via brave://settings/privacy
• Install 1.46.x and upgrade the profile to 1.47.x beta build and ensure that the P3A settings is enabled in brave://settings/privacy and ensured that user can disable the P3A switch via brave://welcome onboarding or brave://settings/privacy settings