Revert "bugfix: ngx.escape_uri: we did not escape URI reserved chars. openresty#1124"

Commit f170505 breaks the compatibility
with RFC 3986. Here is two reasons:
1. Quote from RFC 3986 Section 2.2:
> A subset of the reserved characters (gen-delims) is used as
delimiters of the generic URI components described in Section 3

Note that RFC 3986 says 'a subset of the reserved characters
(gen-delims)', not all the reserved characters. The characters escaped
in that commit are 'sub-delims'. They are not required to be escaped
according to Section 2.2.

2. Refer to RFC 3986 "Appendix A.  Collected ABNF for URI", sub-delims
could be used as part of query and other components. This use case shows
that sub-delims are valid in some component of URI. Therefore, it would
be better if we don't escape them for URI component.

Signed-off-by: Yichun Zhang (agentzh) <agentzh@gmail.com>

Author: spacewander

src/ngx_http_lua_util.c

@@ -1852,7 +1852,7 @@ ngx_http_lua_escape_uri(u_char *dst, u_char *src, size_t size, ngx_uint_t type)
         0xffffffff, /* 1111 1111 1111 1111  1111 1111 1111 1111 */
 
                     /* ?>=< ;:98 7654 3210  /.-, +*)( '&%$ #"!  */
-        0xfc009fff, /* 1111 1100 0000 0000  1001 1111 1111 1111 */
+        0xfc00987d, /* 1111 1100 0000 0000  1001 1000 0111 1101 */
 
                     /* _^]\ [ZYX WVUT SRQP  ONML KJIH GFED CBA@ */
         0x78000001, /* 0111 1000 0000 0000  0000 0000 0000 0001 */

t/006-escape.t

@@ -193,7 +193,7 @@ GET /t
 --- request
 GET /lua
 --- response_body
--_.%21~%2A%27%28%29
+-_.!~*'()
 %2C%24%40%7C%60
 --- no_error_log
 [error]

t/030-uri-args.t

@@ -1403,6 +1403,6 @@ GET /lua
 --- request
 GET /lua
 --- response_body
-args: foo=%2C%24%40%7C%60&bar=-_.%21~%2A%27%28%29
+args: foo=%2C%24%40%7C%60&bar=-_.!~*'()
 --- no_error_log
 [error]