Don't use explicit constructor in copy-initialization.

This aligns "GetTransceivers" with "GetSenders" / "GetReceivers" and
fixes a compilation error if an older libstdc++ from the system is used.

Bug: None
Change-Id: I1cab00549b28c24c2bfdfcef17302db2c70a2fce
Reviewed-on: https://webrtc-review.googlesource.com/90861
Commit-Queue: Joachim Bauch <jbauch@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24128}
diff --git a/api/peerconnectioninterface.cc b/api/peerconnectioninterface.cc
index adae14f..ddaeb36 100644
--- a/api/peerconnectioninterface.cc
+++ b/api/peerconnectioninterface.cc
@@ -98,7 +98,7 @@
 
 std::vector<rtc::scoped_refptr<RtpTransceiverInterface>>
 PeerConnectionInterface::GetTransceivers() const {
-  return {};
+  return std::vector<rtc::scoped_refptr<RtpTransceiverInterface>>();
 }
 
 const SessionDescriptionInterface*