This is the bulk of the changes.
- DisplayItemScrollClip is removed. Instead, we will have 1) ActiveScrolledRoot
and 2) DisplayItemClipChain.
- ActiveScrolledRoot points to a scroll frame and allows traversing up the
scroll frame chain.
- DisplayItemClipChain is a linked list of clips, each clip being associated
with the ActiveScrolledRoot that moves this clip.
- Each display item has an ActiveScrolledRoot and a clip chain.
- nsDisplayItem::GetClip returns the item of the clip chain that scrolls with
the item's ASR. The separation between "regular clip" and "scroll clips"
mostly goes away.
- Tracking clips in the display list builder's clip state happens very
similarly to how regular clips used to be tracked - there's a clip chain for
content descendants and a clip chain for containing block descendants. These
clip chains are intersected to create the combined clip chain.
- There are strict rules for the ASR of a container item: A container item's
ASR should be the innermost ASR which the item has finite clipped bounds with
respect to.
- At some point in the future, ASRs and AGRs should be reunified, but I haven't
done that yet, because I needed to limit the scope of the change.
MozReview-Commit-ID: KYEpWY7qgf2
--HG--
extra : rebase_source : c727f6300a35463750639e165bfa37374c06b851
Prior to this patch, dumping of style contexts in the layout
debugger would only dump the subtree associated with the root
frame, which just covers the viewport, canvas, and associated
scrollbars.
I think this has been broken since bug 236921 (2004) and
bug 378693 (2007) properly disconnected the root element from the
styles for the viewport and canvas.
This patch just manually dumps the root frame and the root
element's frame, since the style set no longer maintains a list
of all of the style context roots.
MozReview-Commit-ID: 5LEnbNtngN2
--HG--
extra : transplant_source : v%BB%09%C8M8%FE%25%A9%A6%3D%EA%BD%BE%DF7%08%9A%85m
The class PresShell doesn't have ns-prefix, so it's better to drop ns-prefix
in the file names to avoid confusion.
MozReview-Commit-ID: IljxsF5CVjh
--HG--
rename : layout/base/nsPresShell.cpp => layout/base/PresShell.cpp
rename : layout/base/nsPresShell.h => layout/base/PresShell.h
extra : rebase_source : e73a6873f360a7223d87bd22d9854fc9603c499f
