Update uses of UTF conversions in content/ to use the base:: namespace.

content/renderer/media/mock_web_rtc_peer_connection_handler_client.cc

Index: content/renderer/media/mock_web_rtc_peer_connection_handler_client.cc
diff --git a/content/renderer/media/mock_web_rtc_peer_connection_handler_client.cc b/content/renderer/media/mock_web_rtc_peer_connection_handler_client.cc
index a50525e1c39cd5edbe3e1b116179032c4b0e2a2d..a4b8e5501339f929a180fa9e8d37d31a3bebce33 100644
--- a/content/renderer/media/mock_web_rtc_peer_connection_handler_client.cc
+++ b/content/renderer/media/mock_web_rtc_peer_connection_handler_client.cc
@@ -32,9 +32,9 @@ MockWebRTCPeerConnectionHandlerClient::
 void MockWebRTCPeerConnectionHandlerClient::didGenerateICECandidateWorker(
     const blink::WebRTCICECandidate& candidate) {
   if (!candidate.isNull()) {
-    candidate_sdp_ = UTF16ToUTF8(candidate.candidate());
+    candidate_sdp_ = base::UTF16ToUTF8(candidate.candidate());
     candidate_mline_index_ = candidate.sdpMLineIndex();
-    candidate_mid_ = UTF16ToUTF8(candidate.sdpMid());
+    candidate_mid_ = base::UTF16ToUTF8(candidate.sdpMid());
   } else {
     candidate_sdp_ = "";
     candidate_mline_index_ = -1;