mergecopies: avoid slowdown from linkrev adjustment (issue4680) checkcopies was using fctx.rev() which it was expecting would be equivalent to linkrev() but was triggering the new _adjustlinkrev path. This was making grafts and merges with large sets of potential copies very expensive.

hgweb: remove an extra call to nodebranchnodefault() in changesetentry() showbranch variable already contains the result of nodebranchnodefault(ctx), so it can be reused.

profile: disable nested report in lsprof by default The nesting makes profiles harder to read and often pushes important data off the end of the report.