implement structured clone callbacks - support Blob cloning
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1. Implement stubs for structured clone callbacks.
2. Support Blob cloning.
Partial implementation of https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm
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Use servo_config::opts only on linux target.
It's not used for other architectures and triggers warnings.
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- [x] These changes fix#16058
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Access browsing context safely
Current browsing context accessor in `Document` unwraps the browsing context `Option` which prevents document to handle correctly the case when there is no browsing context.
This is the reason servo panics with `session-history.max-length=1` (https://github.com/servo/servo/issues/15877).
As it is my first contribution, I added a `safe` method to retrieve the browsing context rather than change the existing method, but I am happy to change if you think this is the right approach. I did not as well replace all existing method call to the `safe` method, to focus on fixing the issue.
If someone can give me a bit of guidance for the test, I will try to contribute one.
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From https://bugzilla.mozilla.org/show_bug.cgi?id=1347719
This effectively combines the discriminants of the two enums and reduces the
size of PropertyDeclaration by one word.
MozReview-Commit-ID: 9rCRiSVZTQT
Implement setter for document.domain
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This PR implements the setter for `document.domain`.
It builds on #15438 and #15478, only the last commit is part of this PR.
It includes tests for similar-origin security checks.
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Implement ImageData constructors #15671 -- 1
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Implement ImageData constructors
* new constructors in the imagedata.rs file
* modification of the ImageData::new method
* new method ImageData::from_vec
* new wpt test file imagedata.html
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Current browsing context accessor in Document unwrap the browsing context option which prevents document to handle correctly the case when there is no browsing context.
Clean up HTMLImageElement::areas
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apply user scripts correctly
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Change while loop in HTMLImageElement::handle_event to for loop
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