Bug 126052

Summary: Avoid checking adjacent rules when doing a Force recalc or if no children changed
Product: WebKit Reporter: Ryosuke Niwa <rniwa>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: benjamin, kling, koivisto
Priority: P2 Keywords: BlinkMergeCandidate
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   

Description Ryosuke Niwa 2013-12-19 21:55:26 PST 
Consider merging https://chromium.googlesource.com/chromium/blink/+/2e53720ae89d22d963aae65fe2de1d4d82cbf3c2

Iterating the children is a waste if we're already going to recalc
everyone like in a Force situation or if we know that no children
needStyleRecalc(). We should skip all the checking in these cases.

I also refactored the loop into checkForChildrenAdjacentRuleChanges()
since recalcChildStyle was getting too long.