Move //mojo/services/X/public/... to //mojo/services/X/... (part 3).

mojo/services/prediction/interfaces/prediction.mojom

 // Copyright 2015 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.
 
 [DartPackage="mojo_services"]
 module prediction;
 
 struct PrevWordInfo {
         string word;
         bool is_beginning_of_sentence;
 };
 
 struct PredictionInfo {
         array<PrevWordInfo> previous_words;
         string current_word;
 };
 
 interface PredictionService {
   GetPredictionList(PredictionInfo prediction_info) => (array<string>? prediction_list);
 };