Guard ChatTipService against disposed scoped context key service

[Copilot]

Unhandled error AbstractContextKeyService has been disposed from ChatTipService._hideShownTipIfNowIneligible -> _isEligible -> contextMatchesRules.

ChatTipService is a singleton that stashes the scoped IContextKeyService of whichever chat widget last requested a welcome tip. When that widget is torn down without resetSession() being called, the scoped service is disposed but the singleton retains the stale reference. The next IChatService.onDidSubmitRequest (a global event fired by any chat widget) then calls contextMatchesRules on the disposed service and throws.

Changes

• chatTipService.ts — Wrap the eligibility check in _hideShownTipIfNowIneligible with try/catch; on throw, drop the stale _contextKeyService and bail (nothing to hide for a torn-down widget).
• chatTipService.test.ts — Regression test: simulate a disposed scoped service by overriding contextMatchesRules to throw the matching error, then assert onDidSubmitRequest does not throw.

let eligible: boolean;
try {
    eligible = this._isEligible(this._shownTip, this._contextKeyService);
} catch (err) {
    // Stored scoped context key service was disposed (owning widget gone).
    this._contextKeyService = undefined;
    return;
}

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• redirector.gvt1.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --no-sandbox --enable-crash-reporter=9e235240-25a7-4aa2-841e-a1b475510a49,no_channel --user-data-dir=/tmp/vscode-tests-1778081838979 --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,2986972629153322651,12185066939970648515,262144 --enable-features=PdfUseShowSaveFilePicker --disable-features=LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TraceSiteInstanceGetProcessCreation --variations-seed-version --trace-process-track-uuid=3190708989122997041 (dns block)
  • Triggering command: ./.build/electron/code-oss ./.build/electron/code-oss --no-sandbox test/unit/electron/index.js --grep disposed --runGlob **/chat/test/**/chatTipService.test.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)