[PATCH 1/2] imagehlp: Catch invalid memory access in CheckSumMappedFile and add tests

[Marvin]

Hi,

While running your changed tests, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?

Full results can be found at:
https://testbot.winehq.org/JobDetails.pl?Key=49960

Your paranoid android.


=== w2008s64 (task log) ===

Task errors:
Unable to set the VM system time: network read timed out (settime/connect:AgentVersion.h:0/9). Maybe the TestAgentd process is missing the required privileges.