improve spec compliance of window.close
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Improve the spec compliance of https://html.spec.whatwg.org/multipage/window-object.html#dom-window-close, mainly by implementing the steps related to [closing a browsing context](https://html.spec.whatwg.org/multipage/window-object.html#close-a-browsing-context)
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Fix for document salvageable state
I noticed a bug where if the document was un-salavageable due to the presence of `beforeunload` listeners, this could be overwritten if there were no listeners for `unload`. This could also have happened if an iframe of the document had no listeners while the parent did.
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move test `dom-element-scroll.html` from mozilla to wpt
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The test `dom-element-scroll.html` was originally landed on #19127.
It was designed for testing `scrollLeft` and `scrollTop`.
It is not only for servo. I thought I put a wrong place at that time. It should not be under `mozilla`. It's better placed under `wpt`.
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Use the color clip corresponding to the last background-image instead
of the last background-clip. (There may be more clips than images and
clips are repeated if there are less clips than images.)
Add a test.
Add an automatic test for border-image-outset with a gradient.
Convert two tests from UTF-8 LE with CRLF line endings to
UTF-8 with LF endings as the old files could not be viewed with servo.
Closes#16638
Make session history aware of URLs
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Move DL items from gfx to layout and implement corner clipping
Implement corner clipping.
Remove PixelFormat from WebrenderImageInfo.
Use WebRender text shadow.
Remove MallocSizeOf and Deserialize for DL items.
Closes#19649, closes#19680, closes#19802
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Implement corner clipping.
Remove PixelFormat from WebrenderImageInfo.
Use WebRender text shadow.
Remove MallocSizeOf and Deserialize for DL items.
Closes#19649, #19680, #19802
