Propagate base minimum delay from video jitter buffer to webrtc/api.

On api level two methods were added to api/media_stream_interface.cc on VideoSourceInterface,
GetLatency and SetLatency. Latency is measured in seconds, delay in milliseconds but both describes
the same concept.


Bug: webrtc:10287
Change-Id: Ib8dc62a4d73f63fab7e10b82c716096ee6199957
Reviewed-on: https://webrtc-review.googlesource.com/c/123482
Commit-Queue: Ruslan Burakov <kuddai@google.com>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26877}
diff --git a/api/media_stream_interface.cc b/api/media_stream_interface.cc
index b55a840..cf994cb 100644
--- a/api/media_stream_interface.cc
+++ b/api/media_stream_interface.cc
@@ -32,7 +32,7 @@
   return {};
 }
 
-double AudioSourceInterface::GetLatency() const {
+double MediaSourceInterface::GetLatency() const {
   return 0.0;
 }