Add convergence_duration to AVCodecParserContext.

Patch by Ivan Schreter, schreter gmx net

Originally committed as revision 17468 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/parser.c

@@ -74,6 +74,7 @@ AVCodecParserContext *av_parser_init(int codec_id)
     s->fetch_timestamp=1;
     s->pict_type = FF_I_TYPE;
     s->key_frame = -1;
+    s->convergence_duration = AV_NOPTS_VALUE;
     return s;
 }