Implement private browsing for mozbrowser
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Support the `mozprivatebrowsing` attribute on mozbrowser iframes. This separates the non-private and private sessions in terms of cookies, HSTS lists, cached HTTP credentials, HTTP connection pools, and web storage. The private session is shared between all private mozbrowsers, and lasts until shutdown.
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Implement non-visible pipeline and iframe visibility methods
This addresses #9566 and a good part of #9751, specifically:
* Pipeline has a notion of visibility
* IFrame setVisible/getVisible interface with IFrame's pipeline visibility
* IFrame mozbrowservisibilitychange responds to changes in visibility
* Pipeline visibility is used to limit animations (requestAnimationFrame does not tick animations when hidden) and to increase timer intervals (currently set to a minimum of 1 second while hidden)
Absent for now are any changes to the Document API and general implementation of the Page Visibility API, since the more interesting parts require knowledge of whether the user agent is minimized, OS screen locked, etc.
cc @paulrouget @jdm
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Fix the type of HTMLIFrameElement.sandbox
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Add support for navigating by a delta
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This adds support for passing a delta with `NavigationDirection`. This will be used with `history.go`
r? @asajeffrey
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Implement meta referrer policy delivery (3)
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Report use statements that use {} with only one entry
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It's a pointless abstraction that propagates the obsolete chan terminology,
swaps the order in which the sender and receiver are returned, and hides a
source of panics.
navigation.
Since WebRender uses the pipeline ID stored in the iframe element to
determine which pipeline to display, it had better be kept up to date!
Closes#9919.
In rust-url 1.0 the `Url` struct is going to have private fields, and there
is no way to to create an aribitrary one without going through the parser.
The plugin never had a clear demonstrated performance benefit,
it was made mostly because it was possible and relatively easy at the time.
This changes headless operation to strictly be a runtime option, rather
than a compile-time one. Note that the old headless version still relied
on a display server to support WebGL, while it now requires one all the
time.
Fixes#8573
