If a minor is found to be a person described in Section 602 by reason of the commission of an offense involving the unlawful possession, use, sale, or other furnishing of a controlled substance, as defined in Chapter 2 (commencing with Section 11053) of Division 10 of the Health and Safety Code, and, unless it makes a finding that this condition would not serve the interests of justice, the court, when recommended by the probation officer, shall require, as a condition of probation, in addition to any other disposition authorized by law, that the minor shall not use or be under the influence of any controlled substance and shall submit to drug and substance abuse testing as directed by the probation officer. If the minor is required to submit to testing and has the financial ability to pay all or part of the costs associated with that testing, the court shall order the minor to pay a reasonable fee, which shall not exceed the actual cost of the testing.