This method is used when updating the SMIL override style and from Web
Animations' Animation.commitStyles method. By using update we accurately return
false when no change is made to a declaration block.
For SMIL this simply acts as an optimization, meaning we can avoid updating the
SMIL override style ub some cases.
For Animation.commitStyles, however, this allows us to avoid generating
a mutation record. Normally making a redundant change to an attribute *does*
generate a mutation record but the style attribute is different. All browsers
avoid generating a mutation record for a redundant change to inline style.
This is specified in the behavior for setProperty[1] which does not update the
style attribute if updated is false.
[1] https://drafts.csswg.org/cssom/#dom-cssstyledeclaration-setproperty
Differential Revision: https://phabricator.services.mozilla.com/D30871
--HG--
extra : moz-landing-system : lando
And also this patch moves some related methods which use the inline methods
and member variables used only by them.
Differential Revision: https://phabricator.services.mozilla.com/D29201
--HG--
rename : layout/base/nsIPresShellInlines.h => layout/base/PresShellInlines.h
extra : moz-landing-system : lando
Summary: Really sorry for the size of the patch. It's mostly automatic
s/nsIDocument/Document/ but I had to fix up in a bunch of places manually to
add the right namespacing and such.
Overall it's not a very interesting patch I think.
nsDocument.cpp turns into Document.cpp, nsIDocument.h into Document.h and
nsIDocumentInlines.h into DocumentInlines.h.
I also changed a bunch of nsCOMPtr usage to RefPtr, but not all of it.
While fixing up some of the bits I also removed some unneeded OwnerDoc() null
checks and such, but I didn't do anything riskier than that.