Fix bug in bytemap computation. Mea culpa.
Fix bug in bytemap computation. Mea culpa.

Change-Id: I2b85597c4c78d68be001576da314513970100633
Reviewed-on: https://code-review.googlesource.com/4766
Reviewed-by: Paul Wankadia <62d4e38bb1380f055ec4b899baa75e52af09c5f7@google.com>

google/re2,google/re2,google/re2,google/re2,google/re2