Do not allocate/copy to a utf-32 string to count a utf-32 len. (#284)
Do not allocate/copy to a utf-32 string to count a utf-32 len. (#284)

* Do not allocate/copy to a utf-32 string to count a utf-32 len.

Resolves a win32 issue of missing char32_t-based codecvt
implementations in their stdlib (win32 favors uchar.)

Signed-off-by: Yechiel Kalmenson <b570fba9aecf1651fa1bd75345294fe6019b6e96@pivotal.io>
Signed-off-by: William A Rowe Jr <6b594a7cef7896b2a5c8742c6f375a4f1966bff1@pivotal.io>
envoyproxy/protoc-gen-validate,envoyproxy/protoc-gen-validate,envoyproxy/protoc-gen-validate,envoyproxy/protoc-gen-validate,envoyproxy/protoc-gen-validate