Double checked BeOS R5 & Haiku R1/A4 and BTextView should be 356
bytes, somewhere since then we've added 4 bytes. So, this commit
reduces the class size from 360 back to 356 by removing 1 reserved
int32 (instead of 2).
I believe the class size changed in hrev46798 as a result of adding
2 bools (1 byte each padded out to 4 bytes).
Sorry for the noise.
d11a323120