make_file: always return a fresh file handle that can be closed
Currently, cmdutil.make_file() will return a freshly made file handle,
except when given a pattern of '-'. If callers would want to close the
handle, they would have to make sure that it's neither sys.stdin or
sys.stdout. Instead, returning a duplicate of either of the two
ensures that make_file() lives up to its name and creates a new
file handle regardless of the input.
subrepo: backed out changeset
2245fcd0e160
bundle progress: offer best-guess deterministic progress information
This uses the same strategy as progress for pulls, estimating manifests
based on changeset count and estimating file count by files list in
each changeset.
httpsendfile: record progress information during read()
This allows us to provide deterministic progress information during
transfer of bundle data over HTTP. This is required because we
currently buffer the bundle data to local disk prior to transfer since
wsgiref lacks chunked transfer-coding support.