Crash while opening brave://sync in incognito

[iefremov]

STR:

1. launch brave, open private or TOR window
2. navigate to brave://sync via omnibox
3. crash

current nightly

Brave	1.26.11 Chromium: 90.0.4430.93 (Official Build) nightly (x86_64)
Revision	4df112c29cfe9a2c69b14195c0275faed4e997a7-refs/branch-heads/4430@{#1348}

current beta

Brave	1.25.53 Chromium: 90.0.4430.93 (Official Build) beta (x86_64)
Revision	4df112c29cfe9a2c69b14195c0275faed4e997a7-refs/branch-heads/4430@{#1348}

https://brave.sp.backtrace.io/p/brave/debug?time=month&filters=((callstack.functions%2Ccontains%2CGetSyncStatusDictionary))&debug=(fb60eb,0)

[ 00 ] signin::IdentityManager::GetPrimaryAccountInfo(signin::ConsentLevel) const
[ 01 ] settings::PeopleHandler::GetSyncStatusDictionary() const
[ 02 ] settings::PeopleHandler::HandleGetSyncStatus(base::ListValue const*)
[ 03 ] content::mojom::WebUIHostStubDispatch::Accept(content::mojom::WebUIHost*, mojo::Message*)
[ 04 ] mojo::InterfaceEndpointClient::HandleValidatedMessage(mojo::Message*)

[iefremov]

cc @AlexeyBarabash @jsecretan

[mariospr]

Just adding some extra info: checked today whether this could have been somehow caused by my mojo migration merged on Friday (see brave/brave-core#8671), but it's not the case (i.e. reverted my changes and still got the crash)

Additionally, I've also checked as per a comment from @iefremov whether the change I proposed in brave/brave-core#8731 could have an impact but, as I already suspected, it doesn't change a thing either.

[pixl8dev]

@iefremov had the same issue

[AlexeyBarabash]

Uplifts are created but current Nightly 1.26.21 doesn't have the fix, will update here once the new Nightly build will be available.

[kjozwiak]

@AlexeyBarabash just double checking, this fix was only for Desktop correct? I can't reproduce the crash using 1.26.21 Chromium: 91.0.4472.57 on Android but can reproduce it easily on Desktop.

[AlexeyBarabash]

@kjozwiak yes, the fix is for Desktop only. On Android there is no crash.

[GeetaSarvadnya]

Verification passed on

Brave | 1.24.86 Chromium: 90.0.4430.212 (Official Build) (64-bit)
-- | --
Revision | e3cd97fc771b893b7fd1879196d1215b622c2bed-refs/branch-heads/4430@{#1429}
OS | Windows 10 OS Version 2004 (Build 19041.985)

• Reproduced the issue in Brave Beta 1.25.53
• Verified the STR from Crash while opening brave://sync in incognito #15717 (comment)
• Ensured there is no crash in PT/TOR/Guest when brave://sync is opened via omnibox

---

Verified passed with

Brave | 1.24.86 Chromium: 90.0.4430.212 (Official Build) (x86_64)
-- | --
Revision | e3cd97fc771b893b7fd1879196d1215b622c2bed-refs/branch-heads/4430@{#1429}
OS | macOS Version 10.15.7 (Build 19H1030)

• Reproduced the issue in 1.24.85
• Verified the STR from Crash while opening brave://sync in incognito #15717 (comment)
• Ensured there is no crash in Normal/PT/TOR/Guest when brave://sync is opened via omnibox

---

Verification passed on

Brave	1.24.86 Chromium: 90.0.4430.212 (Official Build) (64-bit)
Revision	e3cd97fc771b893b7fd1879196d1215b622c2bed-refs/branch-heads/4430@{#1429}
OS	Ubuntu 18.04 LTS

• Reproduced the issue in 1.24.85
• Verified the STR from Crash while opening brave://sync in incognito #15717 (comment)
• Ensured there is no crash in Normal/PT/TOR/Guest when brave://sync is opened via omnibox