8186801: Add regression test to test mapping based charsets (generated at build time)

Reviewed-by: stuefe, sgehwolf
Backport-of: cfe34ed89c4f6ef9a49dceef30da1e43b418b152

Author: gnu-andrew

jdk/make/data/charsetmapping/Big5_HKSCS.c2b

@@ -0,0 +1,16 @@
+#
+0xA15A	0xFF3F #SPACING UNDERSCORE
+0xA1FE	0x2571 #LT DIAG UP RIGHT TO LOW LEFT
+0xA240	0x2572 #LT DIAG UP LEFT TO LOW RIGHTG
+0xA2CC	0x5341 #HANGHZOU NUMERAL TEN
+0xA2CE	0x5345 #HANGZHOU NUMERAL THIRTY
+#
+0xA27E	0x256D	# BOX DRAWINGS LIGHT ARC DOWN AND RIGHT
+0xA2A1	0x256E	# BOX DRAWINGS LIGHT ARC DOWN AND LEFT
+0xA2A2	0x2570	# BOX DRAWINGS LIGHT ARC UP AND RIGHT
+0xA2A3	0x256F	# BOX DRAWINGS LIGHT ARC UP AND LEFT
+0xA2A4	0x2550	# BOX DRAWINGS DOUBLE HORIZONTAL
+0xA2A5	0x255E	# BOX DRAWINGS VERTICAL SINGLE AND RIGHT DOUBLE
+0xA2A6	0x256A	# BOX DRAWINGS VERTICAL SINGLE AND HORIZONTAL DOUBLE
+0xA2A7	0x2561	# BOX DRAWINGS VERTICAL SINGLE AND LEFT DOUBLE
+