SetUnicodeMem in DisplayEngineDxe seems unsafe

["wang xiaofeng" <winggundum82@163.com>]

Hi DisplayEngineDxe  Owner,
   SetUnicodeMem seems unsafe  since the buffer may overflow if the input Size is bigger than buffer size.Do we think about improve the function 


/**
  Set Buffer to Value for Size bytes.


  @param  Buffer                 Memory to set.
  @param  Size                   Number of bytes to set
  @param  Value                  Value of the set operation.


**/
VOID
SetUnicodeMem (
  IN VOID   *Buffer,
  IN UINTN  Size,
  IN CHAR16 Value
  )
{
  CHAR16  *Ptr;


  Ptr = Buffer;
  while ((Size--)  != 0) {
    *(Ptr++) = Value;
  }
}
   
   The problem I meet is liking the following screen. Year in main page shows incorrect char randomly.
    
   If I turn off GetNumericInput optimize with #pragma optimize( "", off ) in InputHandler.c , or swtich to use StrCpyS like this. The problem disappear. This issue cannot be seen in OVMF ,but it can be reproduced in our own platform with a rate of 30%.