ANDROID: Incremental fs: Retry page faults on non-fatal errors

In order to not freeze on corrupt data, we need to turn off
FAULT_FLAG_ALLOW_RETRY. However, this means we no longer retry on EINTR,
so an interrupted read will lead to page faults.

The fault handler does not seem to allow dynamic decisions as to whether
to turn on or off this flag.

To resolve both issues, add a flag to indicate if there are corrupt
pages in a file, and only if there are turn off this flag.

Also fsanitize changed the behavior of mlock - mlock should fail if the
page reads fail, but with fsanitize it returns 0 then page faults on
access. This broke this test, and fsanitize offers little value on test
code, so disable it.

Test: incfs_test passes
Bug: 343532239
Change-Id: Id2ced4be3310109206d65dcc92dea05c05131182
Signed-off-by: Paul Lawrence <paullawrence@google.com>