Fix setting img src before window.onload causing panic
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Setting an image source asynchronously (e.g. using `setTimeout` or in the callback of an `XMLHttpRequest`) before `window.onload` fired would cause a panic due to a preexisting load blocker not being terminated before assigning a new one.
This PR fixes that and adds a test for it.
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In the next few patches we move all non-transition related code over to
using AnimatableLonghand instead of TransitionProperty. This will allow
us to re-purpose TransitionProperty to represent only properties that
can be transitioned (i.e. excluding discrete properties) as well as
simplifying the code by removing the need to deal with shorthands and
the "all" value in places that do not need to handle those values.
This commit also removes the old restyle_hints module and splits it into
multiple modules under components/style/invalidation/element/.
The basic approach is to walk down the tree using compound selectors as needed,
in order to do as little selector-matching as possible.
Bug: 1368240
MozReview-Commit-ID: 2YO8fKFygZI
Don't accept an extra token at the end of transform property
The lack of `input.try` usage makes transform property to accept values like `rotate(70deg)foo`.
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Add pref to force WebGL context creation failure
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Introduces the pref `webgl.testing.context_creation_error`, to force creation of a new WebGLRenderingContext to fail.
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stylo: Bug 1335998 - Handle interpolation and accumulation of mismatched transform lists
These are the interdependent patches of Bug 1335998. We want to do interpolation and accumulation for mismatched transform lists, so introduce ComputedOperation::InterpolateMatrix and ComputedOperation::Accumulation. Both arms store the from_list and to_list, and resolve them until we have the layout information. For the Servo part, we haven't implemented how to read the transform lists in layout/fragment.rs, but I think it would be easy. (related issue #13267)
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The pref `webgl.testing.context_creation_error` will cause creation of a new WebGLRenderingContext to fail, iff set to true.
Also update test expectation of `context_creation_error.html` to pass.
Bump euclid to 0.13 and heapsize to 0.4
This is necessary for the serde 1.0 update.
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Allow style sharing for elements with ids as long as the ID is not being used for styling
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Implement custom element registry
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Implements https://html.spec.whatwg.org/multipage/#customelementregistry
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