fix: don't emit did-fail-load for MediaDocuments

[codebytere]

Description of Change

Closes #37804.

Fixes an issue where successfully loaded media documents emit did-fail-load. We already throw out cancelled navigations in certain places - we want to address the case where it's incorrectly emitted for media documents.

Per spec: when we navigate to a media resource: the original request for the media resource—which resulted in a committed navigation—is simply discarded, while the media element created inside the MediaDocument then makes another new request for the same media resource.

We fix the issue by determining if the ostensible load failure originated from a media document and discard it if it is.

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.

Release Notes

Notes: Fixed an issue where successfully loaded media documents emitted did-fail-load.

[deepak1556]

Possible to have a test ?

[codebytere]

@deepak1556 i thought about it and am not sure - the issue at hand is that the webContents never emits did-finish-load either. So we'd ultimately be checking for an event not being emitted, which isn't really possible to do because there's then nothing to hook on. We could, I suppose, hook onto did-stop-loading? Ideally, we should figure out how to emit did-finish-load correctly but at the moment i'm not quite sure how.

[deepak1556]

What about listening for media-started-playing instead ?

[deepak1556]

Thanks!

[release-clerk]

Release Notes Persisted

Fixed an issue where successfully loaded media documents emitted did-fail-load.

[trop]

I have automatically backported this PR to "22-x-y", please check out #37858

[trop]

I have automatically backported this PR to "24-x-y", please check out #37859

[trop]

I have automatically backported this PR to "23-x-y", please check out #37860