Move proto files back into chrome/browser/policy/proto

chrome/browser/policy/cloud/proto/device_management_local.proto

-// Copyright (c) 2011 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.
-
-syntax = "proto2";
-
-option optimize_for = LITE_RUNTIME;
-
-package enterprise_management;
-
-import "device_management_backend.proto";
-
-// Wrapper around CloudPolicyResponse/DevicePolicyResponse for caching on disk.
-message CachedCloudPolicyResponse {
-  // The DevicePolicyResponse wrapped by this message.
-  optional DevicePolicyResponse device_policy = 1;
-  // Timestamp noting when the |unmanaged| flag was set. The meaning is
-  // milliseconds since 1970. When caching (deprecated) DevicePolicyResponses,
-  // this timestamp also notes when the response was cached.
-  optional uint64 timestamp = 2;
-  // Flag that is set to true if this device is not managed.
-  optional bool unmanaged = 3;
-  // The PolicyFetchResponse wrapped by this message.
-  optional PolicyFetchResponse cloud_policy = 4;
-}
-
-// Encapsulates a device ID and the associated device token.
-message DeviceCredentials {
-  optional string device_id = 1;
-  optional string device_token = 2;
-}