Remove various 'using std::' statements from QUIC code and use

net/quic/core/frames/quic_blocked_frame.cc

Index: net/quic/core/frames/quic_blocked_frame.cc
diff --git a/net/quic/core/frames/quic_blocked_frame.cc b/net/quic/core/frames/quic_blocked_frame.cc
index a7078382038959f9edf4b6820ec4a56ff4ea73a0..3a1046c928b3c82686afada688fcf50a552be148 100644
--- a/net/quic/core/frames/quic_blocked_frame.cc
+++ b/net/quic/core/frames/quic_blocked_frame.cc
@@ -4,14 +4,13 @@
 
 #include "net/quic/core/frames/quic_blocked_frame.h"
 
-using std::ostream;
-
 namespace net {
 
 QuicBlockedFrame::QuicBlockedFrame(QuicStreamId stream_id)
     : stream_id(stream_id) {}
 
-ostream& operator<<(ostream& os, const QuicBlockedFrame& blocked_frame) {
+std::ostream& operator<<(std::ostream& os,
+                         const QuicBlockedFrame& blocked_frame) {
   os << "{ stream_id: " << blocked_frame.stream_id << " }\n";
   return os;
 }