manifest: add rawsize() proxy (API)

I'm not keen about doing this. But it unblocks efforts to remove
"index" from the file storage interface. We will probably remove this
once we have a better upgrade API in place.

Differential Revision: https://phab.mercurial-scm.org/D4718

mercurial/manifest.py

@@ -1569,6 +1569,9 b' class manifestrevlog(object):'
         return self._revlog.addgroup(deltas, linkmapper, transaction,
                                      addrevisioncb=addrevisioncb)
 
+    def rawsize(self, rev):
+        return self._revlog.rawsize(rev)
+
     def getstrippoint(self, minlink):
         return self._revlog.getstrippoint(minlink)
 

mercurial/repository.py

@@ -1136,6 +1136,14 b' class imanifeststorage(interfaceutil.Int'
         See the documentation in ``ifilemutation`` for more.
         """
 
+    def rawsize(rev):
+        """Obtain the size of tracked data.
+
+        Is equivalent to ``len(m.revision(node, raw=True))``.
+
+        TODO this method is only used by upgrade code and may be removed.
+        """
+
     def getstrippoint(minlink):
         """Find minimum revision that must be stripped to strip a linkrev.