QTestlib/selftests: Refactor comparison

The "crashes" subtest has several "expected" reference files. The matching
one was previously determined by checking the line count of the output.

This however does not work when there are several reference files with
identical line count as is now the case with boot2qt.

Refactor the comparison code from the QTest/preliminary void return to
the bool f(QString* errorMessage) convention so that all files can be tried.

While doing so, streamline the code and remove numerous unneeded
allocations of strings and regular expressions per compared line.

Task-number: QTBUG-65845
Change-Id: I722159d1753f2a36f0e497e315ffd81cb58cac0b
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

0 files changed, 0 insertions, 0 deletions