Delete batch mode from VideoProcessorIntegrationTest.

After landing https://codereview.webrtc.org/2997283002/,
batch mode will no longer be needed.

BUG=webrtc:6634

Review-Url: https://codereview.webrtc.org/3005593002
Cr-Original-Commit-Position: refs/heads/master@{#19520}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 9dbd084761208bd161f10a3b3bcb6295339c15e9
4 files changed