merge: only show "cannot merge flags for %s" warning if flags are different

mercurial/merge.py

@@ -475,7 +475,7 b' class mergestate(object):'
         flo = fco.flags()
         fla = fca.flags()
         if 'x' in flags + flo + fla and 'l' not in flags + flo + fla:
-            if fca.node() == nullid:
+            if fca.node() == nullid and flags != flo:
                 if preresolve:
                     self._repo.ui.warn(
                         _('warning: cannot merge flags for %s\n') % afile)

tests/test-merge-types.t

@@ -337,7 +337,6 b' h: l vs l, different'
   merging a
   warning: cannot merge flags for b
   merging b
-  warning: cannot merge flags for bx
   merging bx
   warning: cannot merge flags for c
   merging d
@@ -400,7 +399,6 b' h: l vs l, different'
   merging a
   warning: cannot merge flags for b
   merging b
-  warning: cannot merge flags for bx
   merging bx
   warning: cannot merge flags for c
   merging d