The Servo internal display list items are already pretty much
equivalent to the WebRender ones. Except that Servo items contain
base information and associated glyphs and gradient stops which are
stored implicitly in WebRender. Remove the display items for
rectangles, text, images, border, gradients and box shadow and
replace them with their WebRender counter parts.
Fix crash in DL building
Fix one crash and some style changes.
This HTML crashed servo before. Key parts are `background-clip: content-box` and `direction: rtl`
```html
<!DOCTYPE html>
<html>
<style>
#span1 {
background-clip: content-box;
}
#span2
{
direction: rtl;
}
</style>
<span id="span1">Filler Text <span id="span2">txeT relliF</span></span>
</html>
```
Should I add this as a test? And where do I put this "does-it-crash?" test?
I find always passing rectangles by value a lot easier as it avoids many references and dereferences and I assume that the compiler will always use the faster one either way. If you don't like the change feel free to only merge the first commit.
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Style change in display_list/builder.rs to reduce
the number of & and * found in the code.
Rect<Au> are basically 4 integers so there is no
need to pass by reference.
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
Implement corner clipping.
Remove PixelFormat from WebrenderImageInfo.
Use WebRender text shadow.
Remove MallocSizeOf and Deserialize for DL items.
Closes#19649, #19680, #19802
This uses floating-point (Layout) coordinates in where possible.
Replace NormalBorder struct with WebRender equivalent.
Remove ToPointF and ToRectF traits.
Convert border RepeatKeyword with ToLayout.
Add some definitions to malloc_size_of for WebRender types.
Move display_list_builder.rs and webrender_helpers.rs
along with the new file to components/layout/display_list/
Remove apparently unused IdType enum.
Only variant used was OverflowClip.
See #19676
