A bailee who believes that a thing deposited with him is wrongfully detained from its true owner may give him notice of the bailment; and if, within a reasonable time afterwards, he does not claim it, and sufficiently establish his right thereto, and indemnify the bailee against the claim of the bailor, the bailee is exonerated from liability to the person to whom he gave the notice, upon returning the thing to the bailor, or assuming, in good faith, a new obligation changing his position in respect to the thing, to his prejudice.