switch to nspr types to reduce dependancies on xp_core.h, and fix a warning

mailnews/mime/src/mimemsg.cpp

@@ -464,8 +464,8 @@ HG09091
     PR_FREEIF(charset);
 
 	// setting up truncated message html fotter function
-	char *xmoz = MimeHeaders_get(msg->hdrs, HEADER_X_MOZILLA_STATUS, FALSE,
-								 FALSE);
+	char *xmoz = MimeHeaders_get(msg->hdrs, HEADER_X_MOZILLA_STATUS, PR_FALSE,
+								 PR_FALSE);
 	if (xmoz)
 	{
 		PRUint32 flags = 0;

mailnews/mime/src/nsMsgHeaderParser.cpp

@@ -289,7 +289,7 @@ nsresult nsMsgHeaderParser::ParseHeaderAddresses (const char *charset, const cha
 {
   char *utf8Str, *outStrings;
   MimeCharsetConverterClass *converter = nsnull;
-  nsresult rv;
+  nsresult rv=NS_OK;
 
   if (nsnull == line || MIME_ConvertString(CHARSET(charset), "UTF-8", line, &utf8Str) != 0) {
     utf8Str = nsnull;