Apply GetBestLanguage() for the implementation of HiiStringIdToImage() API.

E.g. L"PlatformLang" variable is "en" and registered string supports "en-US" 

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@7954 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Universal/HiiDatabaseDxe/R8Lib.h

@@ -34,27 +34,6 @@ R8_EfiLibCompareLanguage (
   )
 ;
 
-/**
-  Determine what is the current language setting. The space reserved for Lang
-  must be at least RFC_3066_ENTRY_SIZE bytes;
-
-  If Lang is NULL, then ASSERT.
-
-  @param  Lang                   Pointer of system language. Lang will always be filled with 
-                                 a valid RFC 3066 language string. If "PlatformLang" is not
-                                 set in the system, the default language specifed by PcdUefiVariableDefaultPlatformLang
-                                 is returned.
-
-  @return  EFI_SUCCESS     If the EFI Variable with "PlatformLang" is set and return in Lang.
-  @return  EFI_NOT_FOUND If the EFI Variable with "PlatformLang" is not set, but a valid default language is return in Lang.
-
-**/
-EFI_STATUS
-EFIAPI
-GetCurrentLanguage (
-  OUT     CHAR8               *Lang
-  );
-
 #endif