Motown: Rename Ratio and LinearFunction classes

mojo/services/media/common/cpp/linear_function.cc

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include <limits>
-#include <utility>
-
-#include "mojo/public/cpp/environment/logging.h"
-#include "mojo/services/media/common/cpp/linear_function.h"
-
-namespace mojo {
-namespace media {
-
-// static
-int64_t LinearFunction::Apply(int64_t domain_basis,
-                              int64_t range_basis,
-                              const Ratio& slope,  // range_delta / domain_delta
-                              int64_t domain_input) {
-  return slope.Scale(domain_input - domain_basis) + range_basis;
-}
-
-// static
-LinearFunction LinearFunction::Compose(const LinearFunction& bc,
-                                       const LinearFunction& ab,
-                                       bool exact) {
-  return LinearFunction(ab.domain_basis(), bc.Apply(ab.range_basis()),
-                        Ratio::Product(ab.slope(), bc.slope(), exact));
-}
-
-}  // namespace media
-}  // namespace mojo