Fix non-functional nit in videoadapter

We should DCHECK alignment of width, not height.

BUG=None

Review-Url: https://codereview.webrtc.org/2726543002
Cr-Original-Commit-Position: refs/heads/master@{#16904}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 4e836828f436082179e8d9a4fbf57b7a1a0a9a18
1 file changed