explorerframe/tests: The width is between the RECT left and right fields

[Marvin]

Hi,

While running your changed tests on Windows, 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=24130

Your paranoid android.


=== w7pro64 (64 bit nstc) ===
nstc.c:1946: Test failed: Got event 17, count 1