[P3A] Incorrect value set for WalletBalance [Follow up to #7633]

[srirambv]

Description

[P3A] Incorrect value set for WalletBalance [Follow up to #7633]

Steps to Reproduce

Scenario 1:

1. Clean install 1.3.116
2. Open local-state
3. Brave.Rewards.WalletBalance.2 is set to 0 (as expected)
4. Enable Rewards
5. Brave.Rewards.WalletBalance.2 is set to 2[10-50 BAT, excluding grants] instead of 1[Less than 10 BAT (0-9), excluding grants]

Scenario 2:

1. Clean install 1.3.116
2. Open local-state
3. Brave.Rewards.WalletBalance.2 is set to 0 (as expected)
4. Enable Rewards
5. Brave.Rewards.WalletBalance.2 is set to 2[10-50 BAT, excluding grants] instead of 1[Less than 10 BAT (0-9), excluding grants]
6. Claim UGP grant
7. Brave.Rewards.WalletBalance.2 is set to 3[Over 50 BAT, excluding grants] instead of 1 [Less than 10 BAT (0-9), excluding grants]

Actual result:

Incorrect value set for WalletBalance

Expected result:

Correct values for excluding grants should be set

Reproduces how often:

Easy

Brave version (brave://version info)

Brave	1.3.116 Chromium: 80.0.3987.106 (Official Build) (64-bit)
Revision	f68069574609230cf9b635cd784cfb1bf81bb53a-refs/branch-heads/3987@{#882}
OS	Linux

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

Miscellaneous Information:

Incorrect value is set on current release version as well. May be related to #7235. Issue reproduced on Windows by @GeetaSarvadnya .
cc: @iefremov @rebron

[LaurenWags]

Reproduced on macOS.

Brave	1.3.116 Chromium: 80.0.3987.106 (Official Build) (64-bit)
Revision	f68069574609230cf9b635cd784cfb1bf81bb53a-refs/branch-heads/3987@{#882}
OS	macOS Version 10.14.6 (Build 18G3020)

Restored a wallet with 28 BAT (no grants). Expected "Brave.Rewards.WalletBalance.2" value to be 3 for "10-50 BAT, excluding grants", however it is still displaying 2, even after browser restart.