According to MSDN RegQueryValueEx page:

  If the data has the REG_SZ, REG_MULTI_SZ or REG_EXPAND_SZ type, the
  string may not have been stored with the proper terminating null
  characters. Therefore, even if the function returns ERROR_SUCCESS, the
  application should ensure that the string is properly terminated before
  using it; otherwise, it may overwrite a buffer. (Note that REG_MULTI_SZ
  strings should have two terminating null characters.)

Test written by Alex Brainman <alex.brainman@gmail.com>

Change-Id: I8c0852e0527e27ceed949134ed5e6de944189986
Reviewed-on: https://go-review.googlesource.com/9806Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>