Note: non-inherited properties are stored in "reset" style structs.
Previous implementation treats it as an inherited property, which
doesn't match the spec.
This also fixes the incorrect behavior when using the `unset` value
for this property by specifying SETVAL_UNSET_INITIAL in the mask.
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.
roytam1
MeladJM
Francis Dominic Fajardo
Moonchild
Job Bautista
win7-7
wolfbeast