Add SetJitterBufferMinimumDelay method to RtpReceiverInterface.

This change is required to allow modification of Jitter Buffer delay
in javascript via Origin Trial Experiment.
Link to experiment description:
https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/Tgm4qiNepJc

Bug: webrtc:10287
Change-Id: I4f21380aad5982a4a60c55683b5173ce72ce0392
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/131144
Commit-Queue: Ruslan Burakov <kuddai@google.com>
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27444}
diff --git a/api/rtp_receiver_interface.cc b/api/rtp_receiver_interface.cc
index 52f72df..615a31d 100644
--- a/api/rtp_receiver_interface.cc
+++ b/api/rtp_receiver_interface.cc
@@ -58,4 +58,7 @@
   return nullptr;
 }
 
+void RtpReceiverInterface::SetJitterBufferMinimumDelay(
+    absl::optional<double> delay_seconds) {}
+
 }  // namespace webrtc