ffprobe: fix validity error with tags and data.

Add "data" and "extradata" attributes to the schema.
Add "tag" element in "streams".
Print extradata before tags to avoid closing the element.

Fix trac ticket #1588.

doc/ffprobe.xsd

@@ -44,6 +44,7 @@
       <xsd:attribute name="size"          type="xsd:long" use="required" />
       <xsd:attribute name="pos"           type="xsd:long"  />
       <xsd:attribute name="flags"         type="xsd:string" use="required" />
+      <xsd:attribute name="data"          type="xsd:string" />
     </xsd:complexType>
 
     <xsd:complexType name="frameType">
@@ -86,6 +87,10 @@
     </xsd:complexType>
 
     <xsd:complexType name="streamType">
+      <xsd:sequence>
+        <xsd:element name="tag" type="ffprobe:tagType" minOccurs="0" maxOccurs="unbounded"/>
+      </xsd:sequence>
+
       <xsd:attribute name="index"            type="xsd:int" use="required"/>
       <xsd:attribute name="codec_name"       type="xsd:string" />
       <xsd:attribute name="codec_long_name"  type="xsd:string" />
@@ -94,6 +99,7 @@
       <xsd:attribute name="codec_time_base"  type="xsd:string" use="required"/>
       <xsd:attribute name="codec_tag"        type="xsd:string" use="required"/>
       <xsd:attribute name="codec_tag_string" type="xsd:string" use="required"/>
+      <xsd:attribute name="extradata"        type="xsd:string" />
 
       <!-- video attributes -->
       <xsd:attribute name="width"                type="xsd:int"/>

ffprobe.c

@@ -1844,10 +1844,10 @@ static void show_stream(WriterContext *w, AVFormatContext *fmt_ctx, int stream_i
     else                                print_str_opt("nb_read_frames", "N/A");
     if (nb_streams_packets[stream_idx]) print_fmt    ("nb_read_packets", "%"PRIu64, nb_streams_packets[stream_idx]);
     else                                print_str_opt("nb_read_packets", "N/A");
-    show_tags(stream->metadata);
     if (do_show_data)
         writer_print_data(w, "extradata", dec_ctx->extradata,
                                           dec_ctx->extradata_size);
+    show_tags(stream->metadata);
 
     print_section_footer("stream");
     av_bprint_finalize(&pbuf, NULL);