Revert "Add a frame generator that allows scrolling over a larger still image, for use with new screen sharing quality tests."

This reverts commit 89934133988feaf14fb88f5258f727232a283d0f.

BUG=
R=pbos@webrtc.org

Review URL: https://codereview.webrtc.org/1258803003 .

Cr-Original-Commit-Position: refs/heads/master@{#9653}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 49c0ce359f82b41318e0f8c844db3dd6cba40159
3 files changed