Its filePath() and absoluteFilePath() don't trust its own
isAbsolute(), due to some infelicities on MS-Win; and kludged round a
consequent problem with resource paths; but other virtual file systems
weren't catered for. Replace the convoluted test there with a static
bool function (so that future kludges in this area shall only need to
edit one place; and can document why they're needed) and use a more
robust test that handles all virtual file systems (by asking
QFileInfo) but falls back to QFileSystemEntry to work round the known
infelicities on MS-Win. Add regression test for asset library paths
issue on iOS. Ammends 27f1f84c1c.
Moved a couple of local variables to after the early return, since it
doesn't need them, in the process.
Task-number: QTBUG-70237
Change-Id: Ib3954826df40ccf816beebe5c3751497e3bf6433
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Andy Shaw <andy.shaw@qt.io>
dd5e7f1a52