Reduce log level for socket.SetOptions() to LS_INFO

Bug: webrtc:9221
Change-Id: I7bbbece754afa4e02ab000ee33e2b09ead5647a1
Reviewed-on: https://webrtc-review.googlesource.com/73686
Reviewed-by: Benjamin Wright <benwright@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23197}
diff --git a/p2p/base/p2ptransportchannel.cc b/p2p/base/p2ptransportchannel.cc
index 00f7388..7aa305d 100644
--- a/p2p/base/p2ptransportchannel.cc
+++ b/p2p/base/p2ptransportchannel.cc
@@ -711,9 +711,10 @@
        ++it) {
     int val = port->SetOption(it->first, it->second);
     if (val < 0) {
-      RTC_LOG(LS_WARNING) << port->ToString() << ": SetOption("
-                          << it->first << ", " << it->second
-                          << ") failed: " << port->GetError();
+      // Errors are frequent, so use LS_INFO. bugs.webrtc.org/9221
+      RTC_LOG(LS_INFO) << port->ToString() << ": SetOption(" << it->first
+                       << ", " << it->second
+                       << ") failed: " << port->GetError();
     }
   }