6aa33feadbe11bfa505a80a691d84db966aca134 Drop UpdateTransaction in favor of UpdateInput (Ben Woosley)
Pull request description:
Updating the input explicitly requires the caller to present a mutable
input, which more clearly communicates the effects and intent of the call
(and, often, the enclosing loop).
In most cases, this input is already immediately available and need not be
looked up.
Tree-SHA512: 8c7914a8b7ae975d8ad0e9d760e3c5da65776a5f79d060b8ffb6b3ff7a32235f71ad705f2185b368d9263742d7796bb562395d22b806d90e8502d8c496011e57