Removing a custom filter doesn't restore the blocked element until a browser restart

[Tonev]

Description

Discovered an issue with Brave's Block element feature in Beta and Nightly.

If a user would like to restore a blocked element, they will have to restart the browser in addition to deleting the entry from the Custom Filters field at brave://adblock/.

Steps to Reproduce

1. Install Brave Beta or Brave Nightly.
2. Open a random website, for example brave.com.
3. Block an element using Brave's Block element feature.
4. Open brave://adblock.
5. Delete the entry from the Custom Filters field.
6. Refresh the website you used in the second step.

Actual result:

brave_N3N4kudKKd.mp4

Expected result:

brave_mGTKbsQPcU.mp4

Reproduces how often:

100%

Brave version (brave://version info)

Brave	1.37.97 Chromium: 99.0.4844.74 (Official Build) beta (64-bit)
Revision	fee9a47e86e981802390cb0d41c5ed7ea93c4f6f-refs/branch-heads/4844@{#1060}
OS	Windows 7 Service Pack 1 (Build 7601)

Brave	1.38.60 Chromium: 100.0.4896.46 (Official Build) nightly (64-bit)
Revision	5ca33821b2211805855c77d334353d27c616a7ca-refs/branch-heads/4896@{#584}
OS	Windows 7 Service Pack 1 (Build 7601)

Version/Channel Information:

• Can you reproduce this issue with the current release? No
• Can you reproduce this issue with the beta channel? Yes
• Can you reproduce this issue with the nightly channel? Yes

Miscellaneous Information:

CC: @antonok-edm

[GeetaSarvadnya]

Reproduced the issue on Windows 10 x64 - 1.42.68

Brave | 1.42.68 Chromium: 103.0.5060.114 (Official Build) beta (64-bit)
-- | --
Revision | a1c2360c5b02a6d4d6ab33796ad8a268a6128226-refs/branch-heads/5060@{#1124}
OS | Windows 10 Version 21H2 (Build 19044.1826)

[GeetaSarvadnya]

Elements can be blocked on any website on the Guest window, but removing the custom filter doesn't restore the blocked content until the browser is restarted, if we restart the browser, the guest window session will be lost hence the fix is required. After removing the custom filter, just page reload should restore the blocked content instead of browser restart.