Switching Ads off and then back on stops Ad notifications from showing unless you quit the browser

[tmancey]

Description

Switching Ads off and then back on stops Ad notifications from showing unless you quit the browser

Steps to Reproduce

1. Enable Ads (unless already enabled)
2. Disable Ads
3. Enable Ads

Actual result:

Ads are no longer shown unless you restart the browser

Expected result:

Ads should continue to be shown

Reproduces how often:

Easily reproduced

Brave version (brave://version info)

0.63 and above

Version/Channel Information:

• Can you reproduce this issue with the current release? Yes
• Can you reproduce this issue with the beta channel? Yes
• Can you reproduce this issue with the dev channel? Yes
• Can you reproduce this issue with the nightly channel? Yes

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? N/A
• Does the issue resolve itself when disabling Brave Rewards? Yes
• Is the issue reproducible on the latest version of Chrome? N/A

Miscellaneous Information:

[GeetaSarvadnya]

Verification passed on

Brave	0.68.116 Chromium: 76.0.3809.87 (Official Build) beta (64-bit)
Revision	111fe1e15d5ced26080a7dc239bcfe70f6c49aad-refs/branch-heads/3809@{#967}
OS	Windows 10 OS Version 1803 (Build 17134.523)

• Verified the test plan from Fix switching Ads off and then back on stops Ad notifications from showing unless you quit the browser brave-core#2625

Verification passed on

Brave	0.68.128 Chromium: 76.0.3809.100 (Official Build) beta (64-bit)
Revision	ed9d447d30203dc5069e540f05079e493fc1c132-refs/branch-heads/3809@{#990}
OS	Ubuntu 18.04 LTS

• Verified the test plan from Fix switching Ads off and then back on stops Ad notifications from showing unless you quit the browser brave-core#2625

Verified passed with

Brave	0.68.130 Chromium: 76.0.3809.100 (Official Build) (64-bit)
Revision	ed9d447d30203dc5069e540f05079e493fc1c132-refs/branch-heads/3809@{#990}
OS	Mac OS X

• Verified the test plan from Fix switching Ads off and then back on stops Ad notifications from showing unless you quit the browser brave-core#2625