This adds an additional retry loop in block reflow that we can only
trigger when reflowing a block formatting context (replacedBlock
non-null). It can retry in two different ways, either with a narrower
width but at the same vertical position (when
ReplacedBlockFitsInAvailSpace is still true) or at a new vertical
position (which is treated as a form of clearance).
Fortunately we don't have to worry about margins collapsing *through*
such a boundary since we're dealing with a new block formatting context.
Note that Chromium passes all of the new bfc-displace-* tests, although
it moves the block formating context down unnecessarily in
bfc-shrink-1.html (which we do neither before nor after the patch),
though agrees with the width we have after the patch (but not before the
patch).
--HG--
extra : commitid : FgDc4hjTxHp
L. David Baron