Fix bug #345. The last hit for a file might have been before the last window, so we can't clear copies. To reduce the load, we only store real copy entries instead of storing hashes for every revision.

#!/bin/sh

hg init rep
cd rep
mkdir dir
touch foo dir/bar
hg -v addremove
hg -v commit -m "add 1" -d "1000000 0"
cd dir/
touch ../foo_2 bar_2
hg -v addremove
hg -v commit -m "add 2" -d "1000000 0"