Crash when opening/closing tabs really fast

[NejcZdovc]

Test Plan:

#8227 (comment)

• Open new tab and close fast with middle click. Repeat 20 times.

Original issue description

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

• Describe the issue you encountered:
  When you are opening/closing tabs fast browser reports an error.

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

• Brave Version (revision SHA):
  285ba5e

• Steps to reproduce:

  1. click ctrl + t (to open a new tab) and on the same time click with a middle mouse key to close tab mouse shouldn’t move at all (you should click relatively fast)
  2. after some time around 16 tabs you should get this error

• Actual result:
  

• Expected result:
  No error.

• 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?
  no

• Can this issue be consistently reproduced?
  yes

• Extra QA steps: