In order to tailor certain security checks to the caller that is attempting to
load a particular piece of content, we need to be able to attach an
appropriate triggering principal to the corresponding requests. Since most
HTML content is loaded based on attribute values, that means capturing the
subject principal of the caller who sets those attributes, which means making
it available to AfterSetAttr hooks.
MozReview-Commit-ID: BMDL2Uepg0X
(Path is actually r=froydnj.)
Bug 1400459 devirtualized nsIAtom so that it is no longer a subclass of
nsISupports. This means that nsAtom is now a better name for it than nsIAtom.
MozReview-Commit-ID: 91U22X2NydP
In order to speed up IsDisabled(), instead of querying for the @disabled
attribute, we're now using the NS_EVENT_STATE_DISABLED flag to know whether an
element is disabled.
It is safe to use the NS_EVENT_STATE_DISABLED flag for the following reasons:
- For form elements, nsGenericHTMLFormElement::IsDisabled() is only called on
form elements that can be disabled; form elements that can't be disabled
overrides IsDisabled() to return false directly.
And, before this patch, NS_EVENT_STATE_DISABLED flag is set by
nsGenericHTMLFormElement::IntrinsicState() if and only if IsDisabled() in all
cases when CanBeDisabled() is true, and when CanBeDisabled() is false then
IsDisabled() is always false and the flag is not set.
- For non form elements, optgroup and option have the flag matching
IsDisabled(). Note that option's IsDisabled() should also refer to optgroup's
(if it exists) disabled state, which was not done before this patch.
For this to work correctly, we need to set NS_EVENT_STATE_DISABLED earlier,
that is, in AfterSetAttr(), before any consumer of IsDisabled().
We also need to update the flag whenever the element's parent (e.g. fieldset or
optgroup) disabled state changes and when moving into/out of a parent
container.
Note that NS_EVENT_STATE_DISABLED/ENABLED is now part of the
EXTERNALLY_MANAGED_STATES.
MozReview-Commit-ID: KSceikeqvvU
In order to facilitate the movement of code with side-effects called by Element::SetAttr to Element::BeforeSetAttr and Element::AfterSetAttr, Element::AfterSetAttr should have access to the old value of the attribute. This includes information about whether there was previously a value set or not.
Accomplishing this involved passing an additional argument through functions that find and change the old attribute value in order to ensure that we can differentiate between an empty old value and an absent old value (attribute was not set).
Note that while I tried to ensure that accurate values (and their absence) are reported to Element::AfterSetAttr, I largely ignored SVG. While the old value reported for SVG values should be however accurate the value already being reported to SetAttrAndNotify was, SVG elements do not currently report unset values properly because they will never pass a null pointer to SetAttrAndNotify.
MozReview-Commit-ID: K1mha8CNFZP
The web platform tests changes are just a cherrypick of
https://github.com/w3c/web-platform-tests/pull/2926 so I don't have to add
failure annotations until the next test uplift.
I've audited our uses of nsIFormControl, and this patch looks to me like it
preserves existing behavior in all but the following cases:
1) nsXBLPrototypeHandler::DispatchXBLCommand, the case of scrolling when space
is pressed while something inside a <label> is focused. We used to not scroll
in this situation; I think this is a bug, so I'm changing that behavior to
scroll instead.
2) In Accessible::RelationByType for the RelationType::DEFAULT_BUTTON case,
when mContent is a <label> we used to return its form's default submit element.
Now we will just return Relation().
