revlog: add flags argument to _addrevision, update callers use default flags

For revlog index flags to be useful to other parts of Mercurial, they need to
be settable when writing revisions. The current use case for revlog index
flags is the censorship feature: http://mercurial.selenic.com/wiki/CensorPlan

While the censor flag could be inferred in _addrevision by interrogating the
text/delta being added, that would bury the censorship logic and
inappropriately couple it to all revision creation.

mercurial/revlog.py

@@ -1179,7 +1179,7 b' class revlog(object):'
         ifh = self.opener(self.indexfile, "a+")
         try:
             return self._addrevision(node, text, transaction, link, p1, p2,
-                                     cachedelta, ifh, dfh)
+                                     REVIDX_DEFAULT_FLAGS, cachedelta, ifh, dfh)
         finally:
             if dfh:
                 dfh.close()
@@ -1214,7 +1214,7 b' class revlog(object):'
             return ('u', text)
         return ("", bin)
 
-    def _addrevision(self, node, text, transaction, link, p1, p2,
+    def _addrevision(self, node, text, transaction, link, p1, p2, flags,
                      cachedelta, ifh, dfh):
         """internal function to add revisions to the log
 
@@ -1268,7 +1268,6 b' class revlog(object):'
         base = chainbase = curr
         chainlen = None
         offset = self.end(prev)
-        flags = 0
         d = None
         if self._basecache is None:
             self._basecache = (prev, self.chainbase(prev))
@@ -1399,7 +1398,8 b' class revlog(object):'
 
                 baserev = self.rev(deltabase)
                 chain = self._addrevision(node, None, transaction, link,
-                                          p1, p2, (baserev, delta), ifh, dfh)
+                                          p1, p2, REVIDX_DEFAULT_FLAGS,
+                                          (baserev, delta), ifh, dfh)
                 if not dfh and not self._inline:
                     # addrevision switched from inline to conventional
                     # reopen the index