The result of utf-8 encoding a string was represented in a string, where
each individual character represented a single byte according to its
character code. All usages of this data were interested in the byte
itself, so this required conversion from a character back to its code.
This commit simply stores the individual bytes in array to avoid the
conversion. This yields a ~10% performance improvement for i18n message
ID computation.
PR Close#39694
d281ea820b