dirstate: call the C implementation of nonnonormalentries when available Before this patch, we were using python code for computing the nonnormal dirstate entries. This patch makes us use the C implementation of the function when it is available. Using the nonnormal set in hgwatchman improves hg status performance. Below are the numbers for mozilla-central. with the changes: $ hg perfstatus ! wall 0.010632 comb 0.000000 user 0.000000 sys 0.000000 (best of 246) without the changes: $ hg perfstatus ! wall 0.036442 comb 0.030000 user 0.030000 sys 0.000000 (best of 100) On mozilla-central the improvement to hg status is ~20% (0.25s to 0.2s), on our big repos at Facebook, the win is ~40% (1.2s to 0.72s).