DtlsIdentityStore[Interface/Impl] updated, DtlsIdentityService to be removed

talk/app/webrtc/webrtcsession.cc

Index: talk/app/webrtc/webrtcsession.cc
diff --git a/talk/app/webrtc/webrtcsession.cc b/talk/app/webrtc/webrtcsession.cc
index 5c8b2df754fe8d69dd5928e2a0477e3f2e8e50ab..cf0610362bec81e978298535fa6e8acb982e2e97 100644
--- a/talk/app/webrtc/webrtcsession.cc
+++ b/talk/app/webrtc/webrtcsession.cc
@@ -520,7 +520,7 @@ WebRtcSession::~WebRtcSession() {
 bool WebRtcSession::Initialize(
     const PeerConnectionFactoryInterface::Options& options,
     const MediaConstraintsInterface*  constraints,
-    DTLSIdentityServiceInterface* dtls_identity_service,
+    DtlsIdentityStoreInterface* dtls_identity_store,
     const PeerConnectionInterface::RTCConfiguration& rtc_configuration) {
   bundle_policy_ = rtc_configuration.bundle_policy;
   rtcp_mux_policy_ = rtc_configuration.rtcp_mux_policy;
@@ -534,8 +534,8 @@ bool WebRtcSession::Initialize(
   if (options.disable_encryption) {
     dtls_enabled_ = false;
   } else {
-    // Enable DTLS by default if |dtls_identity_service| is valid.
-    dtls_enabled_ = (dtls_identity_service != NULL);
+    // Enable DTLS by default if we have a |dtls_identity_store|.
+    dtls_enabled_ = (dtls_identity_store != nullptr);
     // |constraints| can override the default |dtls_enabled_| value.
     if (FindConstraint(
           constraints,
@@ -661,7 +661,7 @@ bool WebRtcSession::Initialize(
       signaling_thread(),
       channel_manager_,
       mediastream_signaling_,
-      dtls_identity_service,
+      dtls_identity_store,
       this,
       id(),
       data_channel_type_,