This CL replaces the use of webrtc::Video as an internal variable in the H.264 encoder with the specific fields that are used by this encoder. In support of refactorings discussed around: BUG=600254 Committed: https://crrev.com/2549437b5ccf5aae2e6f1a1491c5f505d1859f9c Review-Url: https://codereview.webrtc.org/2468903003 Cr-Original-Commit-Position: refs/heads/master@{#14887} Cr-Commit-Position: refs/heads/master@{#14892}