Add input length check when fuzzing

Otherwise, the string constructor can walk off the end
looking for a null terminator that never arrives.

Fix some logging copypasta

Bug: skia:
Change-Id: I0cb1b0b75673f64a5ac647307dbc04253f707686
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/199937
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
4 files changed