trace_web_source_location reported a well-formed generated_position past
the end of the selected script as invalid_format on generated_position,
with no bounds, so callers were told their input was malformed and not
which coordinate to change. Report out_of_range on the line or column
that is past the end, with its valid bounds, as export_web_scripts and
inspect_web_network_capture now do for their selections.
The position scan now returns the bound it ran past, so the offset and
the reported limit come from one pass and cannot disagree on line
terminators.
Fixes#7132
amyanger
a9febababc