In rare and pathological circumstances, it could happen that the input
length to the merge function is very short. This CL will avoid one of
the problems with out-of-bounds read that could result from this.
Bug: chromium:799499
Change-Id: I6bde105ae88f9d130764b6dfb3d25443d07e214b
Reviewed-on: https://webrtc-review.googlesource.com/57582
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Commit-Queue: Henrik Lundin <henrik.lundin@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22180}