1. Add conformance checking to ensure the input & output string are well-defined. 2. Adjust the return value of UnicodeStrToAsciiStr() & AsciiStrToUnicodeStr () to be the original destination string to follow MdeLib spec.
1. Add conformance checking to ensure the input & output string are well-defined.
2. Adjust the return value of UnicodeStrToAsciiStr() & AsciiStrToUnicodeStr () to be the original destination string to follow MdeLib spec.

git-svn-id: 5648d1bec6962b0a6d1d1b40eba8cf5cdb62da3d@4653 6f19259b-4bc3-4df7-8a09-765794883524

MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2