Submitted by: @pavel-zotov

Attachments:
broken.fdb.7z
dump-when-connect-to-broken-DB.7z
stack-trace-when-connect-to-broken-DB.7z

Attached .7z files can illustrate the problem:
1) broken.fdb.7z - database which has some pages with arbitrary typed characters (near the beginning of file);
2) stack-trace-when-connect-to-broken-DB.7z and dump-when-connect-to-broken-DB.7z -- stack trace and dump when trying to connect to this DB (checked on LI-V4.0.0.2394)

Commits: f507390 d3ae9f4 98fadc5 81c563d 2573f14 3c99c75

====== Test Details ======

Test implemented but not yet committed to fbt-repo.
To be discussed further, after FB 4.x release.