Convert utility process CheckMediaFile IPC to mojo

chrome/common/extensions/media_parser.mojom

 // Copyright 2017 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.
 
 // Media parsing interface provided by the utility process and exposed by
 // mojo policy control to the chrome browser process.
 
 module extensions.mojom;
 
+import "mojo/common/file.mojom";
+import "mojo/common/time.mojom";
 import "mojo/common/values.mojom";
 
 struct AttachedImage {
   string type;
   array<uint8> data;
 };
 
 interface MediaParser {
   ParseMediaMetadata(string mime_type,
                      int64 total_size,
                      bool get_attached_images)
       => (bool parse_success,
           mojo.common.mojom.DictionaryValue metadata,
           array<AttachedImage> attached_images);
+
+  // Validate the passed media file with sanity checks, and file decoding
+  // for at most |decode_time| wall clock time. Returns |success| true if
+  // |file| appears to be a well-formed media file, false otherwise.
+  // Note: it is still not safe to decode the file in the browser process
+  // after this check.
+  CheckMediaFile(mojo.common.mojom.TimeDelta decode_time,
+                 mojo.common.mojom.File file)
+      => (bool success);
 };