Append the Windows executables suffixes from the PATHEXT
environment variable.
The previous code had a bug since the 'break' statement
bailed out of the inner loop only.
Factor search code out into a separate functions, avoiding
repeated invocations of list.constEnd() and variable
assignments in the old code.
Add a static function that is called on Unix and on Windows
for executable names with a suffix.
Call another function applying a candidate list of suffixes
in case an executable name without a suffix is passed.
Lower case the extensions from PATHEXT, streamline code.
Split up the test, add a _data() slot for clarity.
Task-number: QTBUG-27457
Change-Id: I2bf34de52aeadddd3b937ad1e22191c3c850fd26
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
0e8a2788d8