rollback: lower-case warning issued when branch cannot be reset

Also improved the word order.

mercurial/localrepo.py

@@ -736,8 +736,8 b' class localrepository(repo.repository):'
                     branch = self.opener("undo.branch").read()
                     self.dirstate.setbranch(branch)
                 except IOError:
-                    self.ui.warn(_("Named branch could not be reset, "
-                                   "current branch still is: %s\n")
+                    self.ui.warn(_("named branch could not be reset, "
+                                   "current branch is still: %s\n")
                                  % self.dirstate.branch())
                 self.invalidate()
                 self.dirstate.invalidate()

tests/test-rollback.t

@@ -57,7 +57,7 b' Test rollback of hg before issue 902 was'
   $ rm .hg/undo.branch
   $ hg rollback
   repository tip rolled back to revision -1 (undo commit)
-  Named branch could not be reset, current branch still is: test
+  named branch could not be reset, current branch is still: test
   working directory now based on revision -1
   $ hg branch
   test