Reland "Supporting 48kHz PCM file."

This was first reviewed in https://codereview.webrtc.org/2790493004/.

It got reverted in https://codereview.webrtc.org/2791453004/ due to
upstreaming error.

Bug: None
TBR: niklas.enbom@webrtc.org
Change-Id: Ia5e9bf86e004258b2aa7822bd489d357fcb8f906
Reviewed-on: https://chromium-review.googlesource.com/645634
Reviewed-by: Minyue Li (BackIn2018March) <minyue@webrtc.org>
Commit-Queue: Minyue Li (BackIn2018March) <minyue@webrtc.org>
Cr-Original-Commit-Position: refs/heads/master@{#19642}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 85a3b6b43a479688eb3b05f810f4ec7441cfa4cc