Dataflash log auto anaysis appears to be broken in 1.3.39

I just upgraded MP to 1.3.39. I just installed the update to MP 1.3.39 and realized that the Dataflash auto analysis seems to be broken.
All my .bin files from AC 3.2.1 as well as AC 3.3 and Solo I could auto-analyze in the previous versions of MP result in a "Failed to start LogAnalyzer" followed by a "bad input file" message with this release.
Analyzing with the interactive "Review a log" function works fine however.

Reproduce the failure in Dataflash auto analysis with the reported .bin files from AC 3.2.1, AC 3.3, or Solo, then compare it with the interactive "Review a log" function, which still works. Trace the "Failed to start LogAnalyzer" and "bad input file" messages to identify the affected analysis path; done means auto-analysis accepts these files again.

Written by the indexing model from the issue text.