Fix for https://github.com/wso2/product-iots/issues/1541

[charithag]

Purpose

When a policy with work profile restrictions (In this case system apps that have to be enabled in the work profile) is enabled the android error shows "Invalid operation code received: work profile". This PR fixed that issue and implement missing policy revoke flow for Work Profile policy.
wso2/product-iots#1541

Goals

Implement policy revoke flow for Work Profile policy and improve work profile policy enforcement.

Approach

Modify PolicyRevokeHandler class to restore previous work profile state when Work Profile policy is removed.

User stories

N/A, Bug fix

Release note

This PR will include necessary improvements and changes to apply Work Profile policy correctly and revoke it.

Documentation

N/A, Bug fix

Training

N/A, Bug fix

Certification

N/A, Bug fix

Marketing

N/A, Bug fix

Automation tests

N/A, cannot cover with automations

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines? yes
• Ran FindSecurityBugs plugin and verified report? yes
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets? yes

Samples

N/A, Bug fix

Related PRs

No

Migrations (if applicable)

Directly up-gradable from 3.1.26 release.

Test environment

Android 7.1.1 API 25, emulator

Learning

N/A, Bug fix