disable charset if there is "Content-Encoding" header

src/http/modules/ngx_http_charset_filter_module.c

diff --git a/src/http/modules/ngx_http_charset_filter_module.c b/src/http/modules/ngx_http_charset_filter_module.c
index 850e64e..a5db2d8 100644
--- a/src/http/modules/ngx_http_charset_filter_module.c
+++ b/src/http/modules/ngx_http_charset_filter_module.c
@@ -204,6 +204,12 @@
 
     if (r == r->main) {
 
+        if (r->headers_out.content_encoding
+            && r->headers_out.content_encoding->value.len)
+        {
+            return ngx_http_next_header_filter(r);
+        }
+
         if (r->headers_out.content_type.len == 0) {
             return ngx_http_next_header_filter(r);
         }