Clicking VPN button when logged in sometimes shows expired page

[bsclifton]

Description

The VPN button (top right, next to hamburger menu) is fetching its status each time it's clicked. This takes a while to load and there is a chain of callbacks happening. I suspect there is a problem along the way

https://github.com/brave/brave-core/blob/a36b4979363733d552ee48ccdbf7f2c8e84c740c/components/brave_vpn/brave_vpn_service.cc#L866-L895

1. Sets state to loading
2. Calls CredentialSummary to see if there is a credential
3. Response received; it get parsed and set to failed, expired, not purchased OR it can be valid
4. If valid, PrepareCredentialsPresentation is called to get the actual credentials
5. This credential is used when making calls to Guardian VPN

Related: flickering visible when you click
#21754

Steps to Reproduce

1. Enable VPN (see test plan in Implement Brave VPN on Desktop #15804 for more information)
2. Click VPN button (next to hamburger menu)
3. If it shows the giant toggle, you're good. If it shows an "Expired" screen, that is the problem
4. Repeat steps 2 and 3 until you see the "Expired" screen

Actual result:

Expected result:

It should always show the giant toggle if your VPN is active

[stephendonner]

Verified PASSED using

Brave	1.42.62 Chromium: 103.0.5060.114 (Official Build) beta (x86_64)
Revision	a1c2360c5b02a6d4d6ab33796ad8a268a6128226-refs/branch-heads/5060@{#1124}
OS	macOS Version 11.6.7 (Build 20G630)

Followed the original steps to reproduce (and added some atop).

Confirmed the panel-flashing is fixed, as filed. There are definitely still session-based issues, which manifest as "flashing panel" issues, now. See the Encountered issues section, below.

VPN connected	VPN disconnected	VPN, post-setup	VPN, not-yet set up	too many recovery attempts

Encountered issues:

• Manage Subscription link in about VPN dialog shouldn't open multiple tabs #24048
• Fix credentials fetching from prefs for VPN #23450
• VPN logged-in environment should be cached between browser restarts #24033

---

Verification PASSED on

Brave | 1.42.73 Chromium: 103.0.5060.134 (Official Build) beta (64-bit)
-- | --
Revision | 8ec6fce403b3feb0869b0732eda8bd95011d333c-refs/branch-heads/5060@{#1262}
OS | Windows 10 Version 21H2 (Build 19044.1826)

Confirmed the panel-flashing is fixed, as filed. There are definitely still session-based issues, which manifest as "flashing panel" issues, now. See the Encountered issues section, below.

VPN connected	VPN disconnected	VPN, post-setup	VPN, not-yet set up

• Encountered VPN logged-in environment should be cached between browser restarts #24033