Add a flag to actively reset the SRTP parameters

Add a new flag to RtcConfiguration. By setting that flag to true, the
SRTP parameters will be reset whenever the DTLS transports are reset
after every offer/answer negotiation.

The flag is added to Android and Objc wrapper as well.

This should only be used as a workaround for the linked bug, if the
application knows that the other party is affected (for instance,
using a version number).

TBR=sakal@webrtc.org, denicija@webrtc.org

Bug: chromium:835958
Change-Id: I6db025e1c69bf83e1b1908f7df4627430db9920c
Reviewed-on: https://webrtc-review.googlesource.com/83101
Commit-Queue: Zhi Huang <zhihuang@webrtc.org>
Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23587}
diff --git a/pc/jseptransport.cc b/pc/jseptransport.cc
index ab785af..adce4af 100644
--- a/pc/jseptransport.cc
+++ b/pc/jseptransport.cc
@@ -330,6 +330,15 @@
                           std::string(desc.str()));
 }
 
+void JsepTransport::SetActiveResetSrtpParams(bool active_reset_srtp_params) {
+  if (dtls_srtp_transport_) {
+    RTC_LOG(INFO)
+        << "Setting active_reset_srtp_params of DtlsSrtpTransport to: "
+        << active_reset_srtp_params;
+    dtls_srtp_transport_->SetActiveResetSrtpParams(active_reset_srtp_params);
+  }
+}
+
 void JsepTransport::SetLocalIceParameters(IceTransportInternal* ice_transport) {
   RTC_DCHECK(ice_transport);
   RTC_DCHECK(local_description_);