toLocaleUpperCase() returns string "uppered"

[tero-paananen]

Bug Description

"hello from 0.78".toLocaleUpperCase() returns "uppered" string not "HELLO FROM 0.78" what i was expecting and is returned in React Native Windows 0.77.

React Native Windows version: > 0.77
OS: Windows
Platform (most likely one of arm64-v8a, armeabi-v7a, x86, x86_64): x86_64

Read more from React Native Windows issue: microsoft/react-native-windows#14741

[juhasuni]

The lowercase-version has the same issue:

hermes-windows/lib/Platform/Intl/PlatformIntlWindows.cpp

Line 226 in 6668da2

return std::u16string(u"lowered");

[tero-paananen]

hermes-windows/doc/IntlAPIs.md

Line 199 in d7ca19b

# Windows