This is a code clean up. No functional change intended.

Consolidate the enum for capturer/frame rotation we use through out the code base.

BUG=4145
R=mflodman@webrtc.org, perkj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/39859004

Cr-Original-Commit-Position: refs/heads/master@{#8365}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 5a7dc39277999cbfa0da053da5eacc7fee5cd307