[13] RFR(S): 8223885: hs_err and replay file may contain garbage when overwriting existing file

[Tobias Hartmann]

Hi,

please review the following patch:
https://bugs.openjdk.java.net/browse/JDK-8223885
http://cr.openjdk.java.net/~thartmann/8223885/webrev.00/

With the fix for JDK-8221738 we now overwrite existing hs_err and replay files without truncating
the file. This may lead to garbage at the end of the file if the newly written data requires less
space. Similar to ciEnv::dump_replay_data() and ciEnv::dump_inline_data(), we should open the file
with O_TRUNC to ensure it's properly truncated to zero size.

Thanks,
Tobias