Rewards log not deleted if Rewards are off prior to upgrade - follow up to 11260

[LaurenWags]

Description

Found while testing #11260

If you disable Rewards prior to upgrading to 1.13.x, Rewards.log is not deleted. Once you enable Rewards, then the log file gets removed.

Steps to Reproduce

1. Install 1.12.x, enable Rewards
2. Confirm Rewards.log exists.
3. Turn off Rewards
4. Upgrade to 1.13.x (rename profile if necessary).

Actual result:

Rewards.log file is not purged from profile folder

Expected result:

Logging to be removed

Reproduces how often:

easily

Desktop Brave version:

Brave	1.13.79 Chromium: 85.0.4183.69 (Official Build) dev (64-bit)
Revision	4554ea1a1171bd8d06951a4b7d9336afe6c59967-refs/branch-heads/4183@{#1426}
OS	macOS Version 10.14.6 (Build 18G3020)

Android Device details:

• Install type (ARM, x86):
• Device type (Phone, Tablet, Phablet):
• Android version:

Version/Channel Information:

• Can you reproduce this issue with the current release? n/a
• Can you reproduce this issue with the beta channel? yes
• Can you reproduce this issue with the nightly channel? yes

Other Additional Information:

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

Miscellaneous Information:

cc @NejcZdovc @rebron @mandar-brave @brave/legacy_qa

[LaurenWags]

If this is not applicable to Android please remove OS/Android tag, thanks. cc @srirambv

[NejcZdovc]

closing based on https://bravesoftware.slack.com/archives/CB0KCRCQN/p1598036682009100