Gstreamer plugin README edits
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Updated docs to the gstreamer plugin, now with a recipe for streaming to youtube live!
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Don't delete GL textures created by WebXR
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Currently WebGL assumes it owns any WebGLTexture, and deletes the backing GL texture when the object is GC'd. This isn't valid for textures created by a webxr layer manager, which can result in textures being used after they're deleted.
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Add a pref to indicate user intent to enter webxr
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Add a pref to indicate that the user has indicated intent to enter webxr.
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console.clear implemented
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Layout 2020: Implement basic white-space: pre support
With these changes `<pre>` and `<br>` preserve spaces and force line breaks appropriately.
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Fixed usage of wrong delete
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Layout 2020: Implement `clip: rect`
This implements `clip: rect`
Unfortunately, none of the tests pass yet, they are all broken due to https://github.com/servo/servo/issues/27387
Additionally, currently `clip` does not seem to clip the element itself, only its children. I'm not quite sure what to do about that, I patterned this off of the code in the layout 2013 which handled clip immediately after scroll overflow.
Removed unnecessary conversion from UTF-8 to UTF-16
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Changed Spidermonkey API calls to remove need for UTF-16 conversion.
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Make reload button clear the network cache.
The developer workflow in FxR is frustrating right now because of bugs like https://github.com/servo/servo/issues/24385. To allow us to put out a new release soon that addresses this papercut, these changes make the reload button clear the network cache in FxR.
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Move secondary view support into a pref
Needs https://github.com/servo/webxr/pull/188
Adds a `dom.webxr.first_person_observer_view` pref that toggles FPO views.
