The removal of this preference was botched, all other surrounding plumbing changes appear to be working okay. The ability to use prefs to control this stylesheet might be useful in the future, so perhaps this is one of those "if it ain't broke, don't fix it" bugs where leaving well enough alone in the first place would have been the best choice.
This PR passes all current tests for this feature, and implements the "prefers-color-scheme" media query as an enumerated keyword that is controlled by an integer preference.
Currently, the possible options are 0 to see a website's fallback code and essentially behave like this isn't implemented (our current behavior), 1 to express a preference for a light theme (the default for spec reasons), and 2 to express a preference for a dark theme. Over time, this list may expand to include other preferences like a preference for a sepia theme or something, and this leaves us prepared for that future.
With the changes to layout for WebComponents, it is now apparently possible to
pass in null for frame tree items to this function, which would cause a null
deref crash if not checked.
This feature should not be shipped until the various definitions of addition for
each additive property are properly specified and then implemented accordingly.
Unlike other patches in this series, compositing is not frequently used
internally so there is no need to enable this by default for chrome callers.
ScrollbarStyles contains values of overflow, (over)scroll-behavior, etc.
The only one which is marginally related to scroll _bars_ is overflow, which can
be used to hide scrollbar (by making an element not scrollable) or enforce the
scrollbar to display.
It makes more sense to be called ScrollStyles as it's mainly concerning behavior
of scrolling, not scrollbars. Also, with the addition of scrollbar width
properties, the current name can be confusing.
Overflow properties have two purposes:
1. controlling whether the scrollbar should be shown;
2. controlling whether the content is scrollable.
However, with the scrollbar-width property being added, scrollability and
presence of a scrollbar are no longer tied together.
This patch makes a separation between the value of overflow and the presence of
a scrollbar by making it clear that for ScrollReflowInput, we only care about
whether scrollbar should be shown.
This should make it easier to write the logic involving presence of the
scrollbar based on webdev choice.
While we do fail a couple of tests, the other mainstream browsers also fail them and I think our implementation of tab-size is good enough to be unprefixed at this point. Having this patch also makes testing easier.
Currently -moz-tab-size only accepts <number> values, and both Chrome and Firefox currently support <length> values and have for some time now. So with this you would be able to support sizes in px or em, for instance. This was implemented in Firefox 53 and was trivial to backport.
Mozilla's original implementation of this failed a couple of tests, but this seems to solve all the problems. Basically, the caret-color wasn't able to be set differently based on whether a link was visited, and the auto value implementation was incomplete. The only test we fail now is the one where you have grey text on a grey background and the caret is supposed to be visible, but I think that may have been removed from the spec. Even if it wasn't, no other browser supports it anyway.
This CSS property allows input carets (that blinking input cursor you see in text fields), to be given a custom color. This was implemented in Firefox 53, and it was such a minor feature that no one ever missed it, but I don't see any harm in implementing this.
https://bugzilla.mozilla.org/show_bug.cgi?id=1063162
This actually keeps both pseudo-elements for now, since the prefixed version is
still used internally, but we need the unprefixed version for web compat.
Note: while unprefixing a non-spec-compliant pseudo here, it's exactly in line
with what other browsers do. Nobody is following the spec here and at least
we'll be doing what everyone else is with our unprefixed version.
This aligns with the current spec regarding overflow-wrap: break-word and
overflow-wrap: anywhere in if it affects intrinsic sized due to considering
soft-wrap opportunities or not.
See CSS Text Module Level 3, Editor’s Draft, 1 October 2020, Section 5.5
I got very anxious about making sure I included VARIANT_OPACITY in all the places VARIANT_NUMBER was included to make sure it couldn't possibly break unexpectedly, and that led to me accidentally breaking a mechanism that prevented percentages from serializing as numbers in other parts of the code. It was a total accident, and these additions were unnecessary. Basically, the situation is that there was one part of the code where it determines what's allowed for the flex statement (and possibly other statements) by checking whether it got stored as a "number", and basically only disallows percentages if it attempted to store/serialize them as percentages.
However, it only got to that part of the code because I accidentally allowed VARIANT_OPACITY as a valid way for certain tokens to parse where it wasn't necessary. If it tries to parse it that way under very specific circumstances... percentages will be marked valid and fed through the system as numbers rather than being rejected and not serialized at all, because the check to disallow percentages there relied on them being stored as percentages.
It's a really weird thing to have a problem with in a lot of ways, because if percentages aren't allowed in a field, you would think people wouldn't try to use them there, much less depend on the broken behavior that results from them not parsing as a related value.
Since these are just interpreted comments, there's 0 impact on actual code.
This removes all lines that match /* vim: set(.*)tw=80: */ with S&R -- there are
a few others scattered around which will be removed manually in a second part.
This make MediaQueryList inherit from EventTarget and adds MediaQueryListEvent
as an interface as well as the onchange() method.
This should not affect compatibility with other code; the event object is a
MediaQueryListEvent instance, which is recognized as a MediaListQuery instance.
Even though percentages are already treated as floats internally by the style system for computation purposes, you have to go out of your way to stop them from being read back out as percentages. What I do here amounts to storing the percentage token in the "wrong" container, the one normally used for floats. This allows a value that was read in as a percentage to be read back out as something else, which is normally prevented by the design of the style system.
This preliminary step allows percentages to be computed and display correctly,
but unfortunately it fails a test after changing VARIANT_HN to VARIANT_HPN because that allows values to be serialized as percentages. However, not doing this means percentages are rejected as valid values for the user to input. The way the style system is setup makes it hard to change this for opacity without changing it for everything else, especially since some code-saving speed hacks in Bug 636029 and Bug 441367 that make a lot of assumptions about this stuff very rigid.
Since the local variable is always initialized to false, we don't actually need to declare it and can just pass "false" directly as a parameter to the PrepareSheet function's bool. I was worried about code readability at first, but some well-placed comments took care of that.
This clarifies the assumptions the code is making and the order in which the variables pass through the loading process. The new variable is set after the sheet is created and prepared, and is assumed to be false in the beginning.
There are situations where nsCSSClipPathinstance->CreateClipPath(dt)
returns null. We need to check for this before trying to use its
functions. If there is no clip path, then always return "no hit".
This is just a clean port of 1322191 and follow-up 1325970. It really seems to add create a new way to access existing code relating to block formatting and floating elements rather than implementing new functionality, and it is mercifully straightforwards.
