Make h264_parser_unittest compilable under linux.

content/common/gpu/media/h264_parser.h

 // Copyright (c) 2012 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.
 //
 // This file contains an implementation of an H264 Annex-B video stream parser.
 
 #ifndef CONTENT_COMMON_GPU_MEDIA_H264_PARSER_H_
 #define CONTENT_COMMON_GPU_MEDIA_H264_PARSER_H_
 
 #include <sys/types.h>
@@ skipping 204 matching lines @@
   int slice_beta_offset_div2;
 };
 
 struct H264SEIRecoveryPoint {
   int recovery_frame_cnt;
   bool exact_match_flag;
   bool broken_link_flag;
   int changing_slice_group_idc;
 };
 
-struct H264SEIMessage {
+struct CONTENT_EXPORT H264SEIMessage {
   H264SEIMessage();
 
   enum Type {
     kSEIRecoveryPoint = 6,
   };
 
   int type;
   int payload_size;
   union {
     // Placeholder; in future more supported types will contribute to more
@@ skipping 163 matching lines @@
   typedef std::map<int, H264PPS*> PPSById;
   SPSById active_SPSes_;
   PPSById active_PPSes_;
 
   DISALLOW_COPY_AND_ASSIGN(H264Parser);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_H264_PARSER_H_