Move num_frames from RateProfile to TestConfig struct. Remove methods: SetRateProfile, AddRateControlThresholds. Bug: none Change-Id: I14bcafb8c5b3c1d3b6119417dde038fd82381e3f Reviewed-on: https://webrtc-review.googlesource.com/8540 Commit-Queue: Åsa Persson <asapersson@webrtc.org> Reviewed-by: Rasmus Brandt <brandtr@webrtc.org> Cr-Commit-Position: refs/heads/master@{#20265}