364821 - [FIX]Computed style should never have null style structs

Status: RESOLVED FIXED

(Core :: DOM: CSS Object Model, defect)

Description

[Boris Zbarsky [:bzbarsky]]

Since nsIFrame::GetStyleData and nsStyleContext::GetStyleData never return null, the only way nsComputedDOMStyle::GetStyleData can return null is if we fail to resolve a style context.  So the right thing to do is to resolve that up front if we'll need it, bail if that fails, and skip all the null-checks.

Comment 1

[Boris Zbarsky [:bzbarsky]]

Attachment: Patch

Comment 2

[Boris Zbarsky [:bzbarsky]]

Attachment: Same as diff -w

The interesting changes are in GetStyleData and GetPropertyCSSValue.  The rest is basically null-check removal and ensuing code simplification.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Attachment: Updated to tip

Comment 4

[Boris Zbarsky [:bzbarsky]]

Attachment: Same as diff -w

Comment 5

[Boris Zbarsky [:bzbarsky]]

Attachment: Patch that I checked in

Comment 6

[Boris Zbarsky [:bzbarsky]]

Fixed.