Fixes for r17514 (take two).
Fixes for r17514 (take two).

Actually allocate the right number of comments, and add an extra check against
 i+1 overflowing (which could happen with a 4 GB comment packet on a 64-bit
 machine... unlikely, but possible).


git-svn-id: aaacb87f8b65fb7d6fc622a2ff2a583ecedb130f@17517 0101bb08-14d6-0310-b084-bc0e0c8e3800

soundcloud/tremor,soundcloud/tremor