const unicode/utf8.mask2

3 uses

	unicode/utf8 (current package)
		utf8.go#L37: 	mask2 = 0b00011111
		utf8.go#L181: 		return rune(p0&mask2)<<6 | rune(b1&maskx), 2
		utf8.go#L229: 		return rune(s0&mask2)<<6 | rune(s1&maskx), 2