store: remove uneeded startswith('data/') checks in encodedir() and decodedir()

I don't think we will ever have anything in the store that resides inside a
directory that ends in .i or .d under store/ that we wouldn't want to have
direncoded. The files not under data/ surely don't need direncoding, but it
doesn't harm to let these few run through it. It hurts more to check whether the
thousands of other files start with 'data/'. They do anyway.

See also 810387f59696 (fixed with c31fe74a6633), which moved the direncoding
from filelog into store

mercurial/store.py

@@ -22,8 +22,6 b' def encodedir(path):'
     >>> encodedir('data/foo.i.hg/bla.i')
     'data/foo.i.hg.hg/bla.i'
     '''
-    if not path.startswith('data/'):
-        return path
     return (path
             .replace(".hg/", ".hg.hg/")
             .replace(".i/", ".i.hg/")
@@ -38,7 +36,7 b' def decodedir(path):'
     >>> decodedir('data/foo.i.hg.hg/bla.i')
     'data/foo.i.hg/bla.i'
     '''
-    if not path.startswith('data/') or ".hg/" not in path:
+    if ".hg/" not in path:
         return path
     return (path
             .replace(".d.hg/", ".d/")