Implement beforeunload event and infrastructure
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Implementation of:
1. https://html.spec.whatwg.org/multipage/#prompt-to-unload-a-document, and
2. https://html.spec.whatwg.org/multipage/#unload-a-document
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- [ ] These changes fix#10787 and fix#20485 and fix#20588 and fix#20496 (github issue number if applicable).
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0 is not among the valid values for a wrap mode or filter, so it won't
ever be returned unless the driver is broken, and even if it was a
valid value we would want to pass it through.
Build note for Ubuntu 16.04
See #20712
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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.
Always use border_padding and writing_mode from the same fragment.
Mixing them will trigger a debug assertion if the writing modes are different.
Cleanup and use compute_background_clip
It seems that the result of hash algorithm used in bloom filter depends
on the pointer length. On 64bit platforms, there are 135 false positives
in the first part of that test, and 8 in the second part. However, on
32bit platforms, the numbers become 157 and 16 correspondingly.
16 is still less than 20% in the second part, so all fine, but 157 is
slightly larger than 15% in the test assertion. Given it is what we are
shipping, we probably should just accept this and loosen the assertion.
Bug: 1457524
Reviewed-by: heycam
MozReview-Commit-ID: 9kFXBzLFAzE
Inserting a lot of rules in the root level is super-inefficient. This fixes it
by not doing it.
It gives the root rule node to the style, but that's fine, since it's useless.
All this code-path is already pretty messy.
Bug: 1457678
Reviewed-by: xidorn,hiro
MozReview-Commit-ID: GoGHI4YJbKr
It's not sound to insert random matrices in random positions in the transform
operation list.
I cannot make any sense of what the old code was trying to do.
Bug: 1458715
Reviewed-by: hiro
MozReview-Commit-ID: 5BtCiueEPlR
