144306 - evaluate block dirty reflow coalescing

Status: NEW

(Core :: Layout: Block and Inline, defect)

Description

[Chris Waterson]

In light of the changes to implement the reflow tree (bug 129115), the block's
dirty reflow coalescing may be unnecessary. This bug is a placeholder to
investigate the code simplification and performance ramifications of eliminating it.

Comment 1

[rbs]

Something to keep in the back of the mind is that |ReflowDirtyChild| also has 
the side-benefit of being used as a notification. Thus if you want to do 
something specific when your child will be reflowed, you can do it when your 
child asks you to |ReflowDirtyChild|. Although it wasn't originally meant for 
that, it quickly appeared to have that added advantage, and there is nothing 
else in the nsIFrame API that would allow an ancestor to know beforehand 
if/which/when its descendant is going to be reflowed. It is particularly useful 
for mixed elements where it is cleaner to re-act to changes than to mess (and 
add special cases) in other frames' implementation.

So, if your investigation shows that it can be simplified and collapsed to 
nothingness, its signature might still be kept around for the purpose above.

Comment 2

[Chris Petersen]

Changing priority to P2.

Comment 3

[Boris Zbarsky [:bzbarsky]]

.