1414386 - nsBrowserGlue can uninit BrowserUsageTelemetry before it inits it

Status: RESOLVED FIXED

(Firefox :: General, defect)

Description

[Myk Melez [:myk] [@mykmelez]]

Attachment: ensure BrowserUsageTelemetry is inited before uniniting it

nsBrowserGlue can uninit BrowserUsageTelemetry before it inits it, since it inits it on sessionstore-windows-restored and uninits it on quit-application-granted; and the latter can race the former if the browser quits shortly after startup, before windows have been restored.

When uninit races init, it reports this error:

JavaScript error: resource:///modules/BrowserUsageTelemetry.jsm, line 341: NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIObserverService.removeObserver]

This patch stores the init state in BrowserUsageTelemetry and exists uninit early if it hasn't been inited yet.

(It also makes BrowserUsageTelemetry a weak observer, although that isn't strictly necessary to resolve this issue.)

Comment 1

[Marco Bonardo [:mak]]

Comment on attachment 8925124 [details] [diff] [review]
ensure BrowserUsageTelemetry is inited before uniniting it

Review of attachment 8925124 [details] [diff] [review]:
-----------------------------------------------------------------

LGTM, thanks

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/911d141f1cb1
ensure BrowserUsageTelemetry is inited before uniniting it; r=mak

Comment 3

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/911d141f1cb1