156971 - XUL style attribute changes shouldn't reframe

Status: VERIFIED FIXED

(Core :: CSS Parsing and Computation, defect, P1)

Description

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

XUL style attribute changes currently cause a reframe.  They should be handled
the same way HTML ones are.  I started work on this on bug 156719, but I'm
transferring it here.

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Relevant attachments from bug 156971:
 * patch: attachment 90909 [details] [diff] [review]: see bug 156971 comment 7, bug 156971 comment 11
 * testcase: attachment 90872 [details]:  see bug 156971 comment 10

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Hmm.  That patch seems to cause some crashes.  I need to investigate, but it's
not ready for review...

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: patch

This patch has the crash fixed -- I missed an NS_IF_ADDREF in nsXULElement.cpp.

Comment 4

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

So, a quick summary of the patch:
 * it changes WalkInlineStyleRules to GetInlineStyleRule, which returns a single
style rule.  (Nothing has ever used multiple rules, so we don't need the ability
to return multiple rules.  If we ever do, we could make it an nsISupportsArray
like I suspect it was before hyatt's landing)
 * it changes nsCSSFrameConstructor::AttributeChanged to use GetInlineStyleRule
rather than coding every implementation thereof, over again, by hand.  This
eliminates a large MOZ_SVG section and consolidates an SVG section with an HTML
section.  This code now applies to XUL as well.

Comment 5

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Oh, and, of course, it removes that code to cause a reframe... :-)

Comment 6

[David Hyatt]

I assume the inline style rule will be updated properly across attribute changes...?

Comment 7

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I'm not completely sure what you're asking.  Attribute changes of the "style"
attribute?  What is it that wouldn't get updated?

Comment 8

[David Hyatt]

I just didn't remember there ever being code to store an inline style rule as an 
nsISupports (like HTML does) in XUL.  Maybe I'm just going senile.

sr=hyatt

Comment 9

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 95424 [details] [diff] [review]
patch

mmm. code removal....

r=bzbarsky (and marking the sr=hyatt).

Comment 10

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Fix checked in, 2002-08-16 04:29 PDT.

Comment 11

[Madhur Bhatia]

verified as per developers comments.