revset: implement match() in terms of matchany()

match() is the special case of a single element list being passed
to matchany() with the additional error checking that the revset
spec is defined. Change the implementation to remove the redundant
code and have match() call matchany().

mercurial/revset.py

@@ -2528,13 +2528,10 b' def posttreebuilthook(tree, repo):'
     pass
 
 def match(ui, spec, repo=None):
+    """Create a matcher for a single revision spec."""
     if not spec:
         raise error.ParseError(_("empty query"))
-    lookup = None
-    if repo:
-        lookup = repo.__contains__
-    tree = parse(spec, lookup)
-    return _makematcher(ui, tree, repo)
+    return matchany(ui, [spec], repo=repo)
 
 def matchany(ui, specs, repo=None):
     """Create a matcher that will include any revisions matching one of the