In practice, this is safe since WebRTC doesn't access the buffer after the callback returns. This avoids unnecessary memory allocations causing out of memory errors. Bug: b/72675429 Change-Id: I2ed0224f40b7e1fa67c7aba625b99211f9c1e0a3 Reviewed-on: https://webrtc-review.googlesource.com/49162 Commit-Queue: Sami Kalliomäki <sakal@webrtc.org> Reviewed-by: Magnus Jedvert <magjed@webrtc.org> Cr-Commit-Position: refs/heads/master@{#21932}