convert: make contents of "extra" dict available from sources, for sinks.
This breaks hash preservation for hg->hg conversion, as each converted
change gets a convert_revision item added to its extra dict. Ugh.
findcopies: fix rename bug
We've fiddled with this line several times, and an old bug has
reappeared from it. Let's take a peek at the history.
The original "or" (rev 3674, in 0.9.2 and 0.9.3):
http://www.selenic.com/hg/rev/
9103dab96093
Then I changed it to an "and" to fix a bug (rev 4304):
http://www.selenic.com/hg/rev/
4787e2b0dd03
Then for reasons now lost in the mists of time, I dropped half (rev 4399):
http://www.selenic.com/hg/rev/
93652499bed3
Then we added back the "or" (rev 4416, in 0.9.4):
http://www.selenic.com/hg/rev/
bb1800a7d7e1
So it seems it ought to be "and".