Rename BraveVpnServiceName to BraveVpnHelperName

[spylogsster]

In order to prepare to land implementation of #29253 we need to do some refactorings. BraveVpnHelper is used as BraveVpnService sometimes and would be better to name it as BraveVpnHelper evrywhere

[stephendonner]

Since I'm blocked on Windows 10 by #30291 (thx @MadhaviSeelam !), will do a quick macOS end-to-end test, just as a regression check 👍

[stephendonner]

Verified PASSED using

Brave	1.52.94 Chromium: 113.0.5672.92 (Official Build) beta (x86_64)
Revision	b6f521170062a1fa8a82c33fb223b06fec566da1-refs/branch-heads/5672_63@{#10}
OS	macOS Version 11.7.6 (Build 20G1231)

Steps:

1. installed 1.52.94
2. launched Brave
3. using account.bravesoftware.com, purchased, configured, and connected to Brave VPN
4. changed regions to Brazil
5. loaded browserleaks.com/dns and confirmed no IPv4 or IPv6 DNS-server IP address leaks

Confirmed I could purchase, configure, and connect to Brave VPN

example	example	example	example

[stephendonner]

Verification PASSED using

Brave	1.52.99 Chromium: 113.0.5672.92 (Official Build) beta (64-bit)
Revision	b6f521170062a1fa8a82c33fb223b06fec566da1-refs/branch-heads/5672_63@{#10}
OS	Windows 10 Version 22H2 (Build 19045.2965)

Case 1: Brave VPN helper service auto-start - PASSED

Steps:

1. installed 1.52.99
2. launched Brave
3. purchased, configured, and connected to Brave VPN
4. pressed ctrl + alt + del to open Task Manager
5. confirmed Brave VPN Helper entry in the above
6. confirmed brave_vpn_helper.exe is running, with an additional process to catch its crashes
7. shut down Brave and disconnected from Brave VPN
8. restarted Brave but did NOT connect to Brave VPN

Confirmed brave_vpn_helper.exe service is auto-started when connected to VPN, and is stopped/shut down correctly on both app shut down and app restart

Brave VPN helper dialog	brave_vpn_helper.exe	Brave, shut down	Brave, running, not connected

Case 2: Brave VPN helper service restart - PASSED

Steps:

(continued from Case 1)

1. with Brave running, connected to Brave VPN
2. opened Task Manager
3. confirmed brave_vpn_helper.exe is running
4. selected the helper process
5. clicked on End task
6. confirmed brave_vpn_helper.exe restarted
7. killed the process two more times the same way

Confirmed after killing the helper service, it auto-restarted thrice, and did NOT auto-restart after the 3rd kill

Brave running, w/helper service	Brave running, NO helper service

Case 3: Use Secure DNS settings auto-lock - PASSED

Steps:

1. ran Case 1
2. opened brave://settings/appearance
3. noted the state of Use Secure DNS
4. confirmed in normal operations, with Brave VPN helper service running, Use Secure DNS is checked and the controls are enabled/unlocked
5. ran Case 2
6. opened brave://settings/security
7. confirmed that when Brave VPN helper service is not running any longer, Use Secure DNS is checked but its controls are disabled/locked

Use Secure DNS, unlocked	Use Secure DNS, locked

Case 4: No DNS leaks - PASSED

Steps:

1. ran Case 1
2. loaded browserleaks.com/dns
3. noted no DNS IP-address leaks from my ISP
4. ran Case 2
5. loaded browserleaks.com/dns
6. noted no DNS IP-address leaks from my ISP

example	example

[MadhaviSeelam]

Verification PASSED using

Brave | 1.52.102 Chromium: 113.0.5672.126 (Official Build) beta (64-bit)
-- | --
Revision | c541687b21a73452ab403e2dced7033ddc97ee9d-refs/branch-heads/5672@{#1202}
OS | Windows 11 Version 22H2 (Build 22621.1702)

Case 1: Brave VPN helper service auto-start - PASSED

Steps:

1. installed 1.52.102
2. launched Brave
3. purchased, configured, and connected to Brave VPN
4. pressed ctrl + alt + del to open Task Manager
5. confirmed Brave VPN Helper entry in the above
6. confirmed brave_vpn_helper.exe is running, with an additional process to catch its crashes
7. disconnected from Brave VPN and close Brave
8. restarted Brave but did NOT connect to Brave VPN
9. verified Brave VPN Helper entry is not shown
10. Connected to VPN

Confirmed brave_vpn_helper.exe service is auto-started when connected to VPN, and is stopped/shut down correctly on both app shut down and app restart

VPN panel not connected	brave_vpn_helper.exe not shown	brave_vpn_helper.exe	brave shutdown	Brave, running, not connected

Case 2: Brave VPN helper service restart - PASSED

Steps:

(continued from Case 1)

1. with Brave running, connected to Brave VPN
2. opened Task Manager
3. confirmed brave_vpn_helper.exe is running
4. selected the helper process
5. clicked on End task
6. confirmed brave_vpn_helper.exe restarted
7. killed the process two more times the same way

Confirmed after killing the helper service, it auto-restarted thrice, and did NOT auto-restart after the 3rd kill

Brave running, w/helper service	Step 5	Brave running, NO helper service

Case 3: Use Secure DNS settings auto-lock - PASSED

Steps:

1. ran Case 1
2. opened brave://settings/appearance
3. noted the state of Use Secure DNS
4. confirmed in normal operations, with Brave VPN helper service running, Use Secure DNS is checked and the controls are enabled/unlocked
5. ran Case 2
6. opened brave://settings/security
7. confirmed that when Brave VPN helper service is not running any longer, Use Secure DNS is checked but its controls are disabled/locked

Use Secure DNS, unlocked	Use Secure DNS, locked

Case 4: No DNS leaks - PASSED

Steps:

1. ran Case 1
2. loaded browserleaks.com/dns
3. noted no DNS IP-address leaks from my ISP
4. ran Case 2
5. loaded browserleaks.com/dns
6. noted no DNS IP-address leaks from my ISP

example	example