const unicode/utf8.mask3

3 uses

	unicode/utf8 (current package)
		utf8.go#L38: 	mask3 = 0b00001111
		utf8.go#L182: 		return rune(p0&mask3)<<12 | rune(b1&maskx)<<6 | rune(b2&maskx), 3
		utf8.go#L230: 		return rune(s0&mask3)<<12 | rune(s1&maskx)<<6 | rune(s2&maskx), 3