commit 247bafd09cd08fbd53f9e678a23c829cd5b7e2df
author Ming-Ying Chung <mych@chromium.org> Tue Sep 20 05:07:29 2022
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Sep 20 05:07:29 2022
tree 12dc90b65882a32b5825d6beb089529abed0e231
parent 2d0eced06255127e471d100b4bc34f5242d2524b

[beacon-api] Fix renderer crashes caused by accessing unbound remote

- Stacktrace: https://crbug.com/1364348#c5
- Details Explained: https://crbug.com/1364348#c7

When a document is unloaded, it's possible that a `PendingBeacon`'s `timeout_timer_` stays alive even after the ExecutionContext is gone (detached). In such case, `PendingBeacon::TimeoutTimerFired()` will lead to a crash due to accessing `remote_` which is unbound.

The crash can be reliably reproduced by setting a short timeout in PendingGetBeacon ctor and unloads the document quickly.
(But still not sure why a PendingGetBeacon() with default (negative) timeout can trigger `TimeoutTimerFired()`.)

This CL makes `PendingBeacon` implements
`ExecutionContextLifecycleObserver` and handles such case in
`ContextDestroyed()` method.

Also updates the sendondiscard web tests:
- Before: PendingPostBeacon was not covered. Beacons with different timeout/backgroundTimeout were not covered.
- After: better cover the behaviors of sending beacons on page discard with different timeout/backgroundTimeout values (which should not be used at all though)

Bug: 1364348,1293679
Change-Id: I44edc6ddde20c75f8bbcca0d2b452504517530b1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3901567
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: Ming-Ying Chung <mych@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1048952}