filelog: stop proxying deltaparent() (API)
deltaparent() obtains the revision number of the base revision a
delta in storage is stored against. It is highly revlog-centric and
may not apply to other storage backends. As a result, it doesn't
belong on the generic file storage interface.
This method/proxy is no longer used in core. The last consumer was
probably changegroup code and went away with the transition to
emitrevisions().
Differential Revision: https://phab.mercurial-scm.org/D4751
{
"version": 1,
"project": "mercurial",
"project_url": "https://mercurial-scm.org/",
"repo": "..",
"branches": ["default", "stable"],
"environment_type": "virtualenv",
"show_commit_url": "https://www.mercurial-scm.org/repo/hg/rev/",
"benchmark_dir": "benchmarks",
"env_dir": "../.asv/env",
"results_dir": "../.asv/results",
"html_dir": "../.asv/html"
}