Fix for declaration of functions

mailnews/mime/cthandlers/calendar/mimecal.cpp

@@ -43,13 +43,13 @@ extern int MK_OUT_OF_MEMORY;
 MimeDefClass(MimeInlineTextCalendar, MimeInlineTextCalendarClass,
              mimeInlineTextCalendarClass, NULL);  
 
-PUBLIC char *
+extern "C" char *
 MIME_GetContentType(void)
 {
   return CAL_CONTENT_TYPE;
 }
 
-PUBLIC MimeObjectClass *
+extern "C" MimeObjectClass *
 MIME_CreateContentTypeHandlerClass(const char *content_type, 
                                    contentTypeHandlerInitStruct *initStruct)
 {

mailnews/mime/src/mimecth.h

@@ -143,12 +143,14 @@ extern MimeMultipartSignedClass  *MIME_GetmimeMultipartSignedClass(void);
  * MIME_GetContentType() is called by libmime to identify the content
  * type handled by this plugin.
  */ 
+extern "C" 
 char            *MIME_GetContentType(void);
 
 /* 
  * This will create the MimeObjectClass object to be used by the libmime
  * object system.
  */
+extern "C" 
 MimeObjectClass *MIME_CreateContentTypeHandlerClass(const char *content_type, 
                                    contentTypeHandlerInitStruct *initStruct);