Set a limit on the size for BMP images

This limit matches the limit used by Chromium. I am not aware of any
real world BMPs that are larger than this (or even close to it), but
there are some invalid BMPs that are larger than this, leading to
crashes when we try to read a row.

BUG:34778578
BUG=skia:3617

Change-Id: I0f662e8d0d7bc0b084e86d0c9288b831e1b296d7
Reviewed-on: https://skia-review.googlesource.com/8966
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
3 files changed