Added extra bool in Window object to know about its Mutation Observers
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- Added Cell<bool> type variable in Window object to know whether its mutation observers are present/absent
- Added get and set functions for this variable
- Added supporting test files to check for performance
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- [x] These changes fix#16936.
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It's just a struct aggregating stylesheets + CascadeData, with a quirks_mode
parameter because XBL sucks so bad.
Bug: 1436059
Reviewed-by: xidorn
MozReview-Commit-ID: 7q99tSNXo0K
Implement element.innerText setter
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#16107
- [X] There are tests for these changes
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The TextInput::assert_ok_selection() method is meant to ensure that we
are not getting into a state where a selection refers to a location in
the control's contents which doesn't exist.
However, before this change we could have a situation where the
internals of the TextInput are changed by another part of the code,
without using its public API. This could lead to us having an invalid
selection.
I did manage to trigger such a situation (see the test added in this
commit) although it is quite contrived. There may be others that I
didn't think of, and it's also possible that future changes could
introduce new cases. (Including ones which trigger panics, if indexing
is used on the assumption that the selection indices are always valid.)
The current HTML specification doesn't explicitly say that
selectionStart/End must remain within the length of the content, but
that does seems to be the consensus reached in a discussion of this:
https://github.com/whatwg/html/issues/2424
The test case I've added here is currently undefined in the spec which
is why I've added it in tests/wpt/mozilla.
It only has one use, has the same effect that "auto", and should have no effect
in <a> elements anyway (plus it's not overridden or used in that file at all
anyway), so we can remove its only use instead.
I can also change that use to "auto" if you want, but bug 760876 doesn't mention
-moz-user-input at all, so I think this is quite useless...
See the intent to unship for research on out of the tree usage:
https://groups.google.com/d/msg/mozilla.dev.platform/E6tfP__wkwg/YVW6nPX9CQAJ
Bug: 1405087
Reviewed-by: bz
MozReview-Commit-ID: 8EzQlzu9drE
