Fix bug #46944 - UTF-8 characters outside the BMP aren't encoded correctly.

Author: Scott MacVicar

ext/json/utf8_decode.c

@@ -159,7 +159,7 @@ int utf8_decode_next(json_utf8_decode *utf8) /* {{{ */
 	/*
 	   Three continuation (65536 to 1114111)
 	   */
-	if ((c & 0xF1) == 0xF0) {
+	if ((c & 0xF8) == 0xF0) {
 		int c1 = cont(utf8);
 		int c2 = cont(utf8);
 		int c3 = cont(utf8);

ext/json/utf8_to_utf16.c

@@ -45,7 +45,7 @@ int utf8_to_utf16(unsigned short w[], char p[], int length)  /* {{{ */
 			w[the_index] = (unsigned short)c;
 			the_index += 1;
 		} else {
-			c &= 0xFFFF;
+			c -= 0x10000;
 			w[the_index] = (unsigned short)(0xD800 | (c >> 10));
 			the_index += 1;
 			w[the_index] = (unsigned short)(0xDC00 | (c & 0x3FF));