clfilter: ensure cache invalidation is done on the main unfiltered repo

The proxy version will not hold any cache for now. But we have to ensure
all cache operations are done on the unfiltered version.

mercurial/localrepo.py

@@ -1075,16 +1075,17 b' class localrepository(object):'
                     delattr(self.dirstate, k)
                 except AttributeError:
                     pass
-            delattr(self, 'dirstate')
+            delattr(self.unfiltered(), 'dirstate')
 
     def invalidate(self):
+        unfiltered = self.unfiltered() # all filecaches are stored on unfiltered
         for k in self._filecache:
             # dirstate is invalidated separately in invalidatedirstate()
             if k == 'dirstate':
                 continue
 
             try:
-                delattr(self, k)
+                delattr(unfiltered, k)
             except AttributeError:
                 pass
         self.invalidatecaches()
@@ -1489,6 +1490,7 b' class localrepository(object):'
                 tr.release()
             lock.release()
 
+    @unfilteredmeth
     def destroyed(self, newheadnodes=None):
         '''Inform the repository that nodes have been destroyed.
         Intended for use by strip and rollback, so there's a common