This CL: - Renames the ViEEncoder class to VideoStreamEncoder, according to discussions. - Renames variables 'vie_encode' to 'video_stream_encoder'. - Formatting to match style guide. - No other changes. BUG=webrtc:8064 Review-Url: https://codereview.webrtc.org/2995433002 Cr-Commit-Position: refs/heads/master@{#19237}