Fixed nb_stream variable in resultdesc and fixed test to detect change between two media descs

coreapi/offeranswer.c

@@ -564,6 +564,7 @@ int offer_answer_initiate_incoming(const SalMediaDescription *local_capabilities
 					SalMediaDescription *result, bool_t one_matching_codec){
 	int i;
 	const SalStreamDescription *ls=NULL,*rs;
+	result->nb_streams = 0;
 
 	for(i=0;i<SAL_MEDIA_DESCRIPTION_MAX_STREAMS;++i){
 		rs=&remote_offer->streams[i];
@@ -588,6 +589,7 @@ int offer_answer_initiate_incoming(const SalMediaDescription *local_capabilities
 					result->streams[i].rtcp_xr.enabled = TRUE;
 				}
 			}
+			result->nb_streams++;
 		}else {
 			ms_message("Declining mline %i, no corresponding stream in local capabilities description.",i);
 			/* create an inactive stream for the answer, as there where no matching stream in local capabilities */
@@ -603,7 +605,7 @@ int offer_answer_initiate_incoming(const SalMediaDescription *local_capabilities
 			}
 		}
 	}
-	result->nb_streams=i;
+
 	strcpy(result->username, local_capabilities->username);
 	strcpy(result->addr,local_capabilities->addr);
 	result->bandwidth=local_capabilities->bandwidth;

coreapi/sal.c

@@ -342,7 +342,7 @@ int sal_media_description_equals(const SalMediaDescription *md1, const SalMediaD
 	if (md1->nb_streams != md2->nb_streams) result |= SAL_MEDIA_DESCRIPTION_STREAMS_CHANGED;
 	if (md1->bandwidth != md2->bandwidth) result |= SAL_MEDIA_DESCRIPTION_CODEC_CHANGED;
 	for(i = 0; i < SAL_MEDIA_DESCRIPTION_MAX_STREAMS; ++i){
-		if (!sal_stream_description_active(&md1->streams[i]) || !sal_stream_description_active(&md2->streams[i])) continue;
+		if (!sal_stream_description_active(&md1->streams[i]) && !sal_stream_description_active(&md2->streams[i])) continue;
 		result |= sal_stream_description_equals(&md1->streams[i], &md2->streams[i]);
 	}
 	return result;