Add WebGLSampler support
Reference: https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.13
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cc @jdm @zakorgy
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Allow using CORS filtered image responses as WebGL textures
More specifically, this makes the "is this image same origin?" check consider the CORS status of the original response, rather than relying on an overly-strict "is this image's response's URL same-origin with a particular global?" check. To do this, we make the image cache double keyed based on the requested URL as well as the requesting origin, and store the CORS status of the eventual response with the final image that eventually gets sent to the HTMLImageElement consumer.
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There are a few canvas2d-related dependencies that haven't updated, but they
only use euclid internally so that's not blocking landing the rest of the
changes.
Given the size of this patch, I think it's useful to get this landed as-is.
Preliminary WebXR support
This implements just enough WebXR to display to 3DOF devices in
immersive mode only.
Couple missing things:
- [ ] Handling reference spaces (even if just supporting eye-level spaces)
- [x] Spec links
- [ ] We enter immersive mode when baseLayer is set, but it seems like
we're supposed to do this when requestSession is called (https://github.com/immersive-web/webxr/issues/453)
- [ ] VR/XR should block less (https://github.com/servo/servo/issues/22505)
- [x] More pref-gating
- [x] `views` is a method instead of an attribute because we don't support FrozenArray
<s>Once I add spec links and pref gating</s> this can be landed as-is for further experimentation.
r? @jdm @MortimerGoro
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Add GetShaderPrecisionFormat argument validation
This patch adds a check on the shader_type argument. If it is not one either
FRAGMENT_SHADER or VERTEX_SHADER, we return INVALID_ENUM.
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