Sort indicator is not shown next to the table heading in about:preferences#extensions

[srirambv]

Testing Plan

#8222 (comment)

Navigate to about:preferences#extensions
Click the Enabled column header
Note that sorting has been disabled

Original issue description

• Did you search for similar issues before submitting this one?
  Yes

• Describe the issue you encountered:
  Sort indicator is not shown next to the table heading in about:preferences#extensions

• Platform (Win7, 8, 10? macOS? Linux distro?):
  All

• Brave Version (revision SHA):
  Brave 0.14.2
  rev 61ae1a7

• Steps to reproduce:

  1. Open about:preferences#extension
  2. Click on the table heading to sort the list
  3. Sort indicator is shown below the text which looks awkward

• Actual result:
  Sort indicator is not shown next to the table heading in about:preferences#extensions

• Expected result:
  Should show the sort indicator next to the table heading

• Will the steps above reproduce in a fresh profile? If not what other info can be added?
  Yes

• Is this an issue in the currently released version?
  N/A

• Can this issue be consistently reproduced?
  Yes

• Extra QA steps:
  1.
  2.
  3.

• Screenshot if needed:
  

• Any related issues:
  cc: @cezaraugusto

[cezaraugusto]

/cc @jonathansampson that's related to convo we had on Slack, mind grabbing? just need to add sortingDisabled to sortableTable

[jonathansampson]

@cezaraugusto Just got back to a computer; I'll take it! :)