fix build when ffmpeg, libvpx and libwebm are disabled

chrome/utility/media_galleries/media_metadata_parser.cc

 // Copyright 2013 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 "chrome/utility/media_galleries/media_metadata_parser.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 38 matching lines @@
 
 // This runs on |media_thread_|, as the underlying FFmpeg operation is
 // blocking, and the utility thread must not be blocked, so the media file
 // bytes can be sent from the browser process to the utility process.
 void ParseAudioVideoMetadata(
     media::DataSource* source, bool get_attached_images,
     MediaMetadataParser::MediaMetadata* metadata,
     std::vector<AttachedImage>* attached_images) {
   DCHECK(source);
   DCHECK(metadata);
+
+#if !defined(MEDIA_DISABLE_FFMPEG)
   media::AudioVideoMetadataExtractor extractor;
 
   if (!extractor.Extract(source, get_attached_images))
     return;
 
   if (extractor.duration() >= 0)
     metadata->duration.reset(new double(extractor.duration()));
 
   if (extractor.height() >= 0 && extractor.width() >= 0) {
     metadata->height.reset(new int(extractor.height()));
@@ skipping 32 matching lines @@
   if (get_attached_images) {
     for (std::vector<std::string>::const_iterator it =
              extractor.attached_images_bytes().begin();
          it != extractor.attached_images_bytes().end(); ++it) {
       attached_images->push_back(AttachedImage());
       attached_images->back().data = *it;
       net::SniffMimeTypeFromLocalData(it->c_str(), it->length(),
                                       &attached_images->back().type);
     }
   }
+#endif
 }
 
 void FinishParseAudioVideoMetadata(
     MediaMetadataParser::MetadataCallback callback,
     MediaMetadataParser::MediaMetadata* metadata,
     std::vector<AttachedImage>* attached_images) {
   DCHECK(!callback.is_null());
   DCHECK(metadata);
   DCHECK(attached_images);
 
@@ skipping 68 matching lines @@
         source_,
         base::Bind(&FinishParseImageMetadata, base::Owned(extractor),
                    mime_type_, callback));
     return;
   }
 
   callback.Run(MediaMetadata(), std::vector<AttachedImage>());
 }
 
 }  // namespace metadata