Fixing the change in number of temporal layers in screen sharing mode.
Fixing the change in number of temporal layers in screen sharing mode.

Number of temporal layers in screen sharing was unintentionally changed
from 3 to 2 in a796a7ee85b8805a92e21f888a893bef1581bfee.

This changes the value to 3.

Bug: webrtc:9013
Change-Id: I68291b49276afd2689f20d1c3581e149aa6fd610
Reviewed-on: https://webrtc-review.googlesource.com/61860
Reviewed-by: Erik Språng <3ab8c90c99d6dd7822e0fad803ab0211dd287ae5@webrtc.org>
Reviewed-by: Stefan Holmer <eb0877843acc39f8ef6f7269937dee931c372d23@webrtc.org>
Commit-Queue: Sergey Silkin <fc631354f276613a5410ea259cf4618b2846d39b@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#22621}
TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc