(a) A provision treating a corporation's indemnification of or advance for expenses to directors that is contained in its articles of incorporation, bylaws, a resolution of its members or board of directors, or in a contract or otherwise, is valid only if and to the extent the provision is consistent with this part. If articles of incorporation limit indemnification or advance for expenses, indemnification and advance for expenses are valid only to the extent consistent with the articles.
(b) This part does not limit a corporation's power to pay or reimburse expenses incurred by a director in connection with appearing as a witness in a proceeding at a time when the director has not been made a named defendant or respondent to the proceeding.