wininet: Properly set flags in InternetSetOption(INTERNET_OPTION_SECURITY_FLAGS).
diff --git a/dlls/wininet/http.c b/dlls/wininet/http.c
index b123283..e263d8a 100644
--- a/dlls/wininet/http.c
+++ b/dlls/wininet/http.c
@@ -2197,10 +2197,11 @@
         if (!buffer || size != sizeof(DWORD))
             return ERROR_INVALID_PARAMETER;
         flags = *(DWORD *)buffer;
-        TRACE("%08x\n", flags);
-        req->security_flags = flags;
+        TRACE("INTERNET_OPTION_SECURITY_FLAGS %08x\n", flags);
+        flags &= SECURITY_SET_MASK;
+        req->security_flags |= flags;
         if(req->netconn)
-            req->netconn->security_flags = flags;
+            req->netconn->security_flags |= flags;
         return ERROR_SUCCESS;
     }
     case INTERNET_OPTION_CONNECT_TIMEOUT: