
Required to permit conversion of NV12 handles on iOS to I420 for VP8 software encoding, which blocks texture-based capture. This change enforces that all texture-based input provides a method for converting native handles to I420 if they are ever used with software encoders that do not understand the native handles. BUG=4081 R=emircan@chromium.org, glaznev@webrtc.org, hbos@webrtc.org, magjed@webrtc.org, mflodman@webrtc.org, stefan@webrtc.org, tkchin@webrtc.org Review URL: https://webrtc-codereview.appspot.com/50909005 Cr-Commit-Position: refs/heads/master@{#9347}