Backed out changeset 8597b133717f (bug 1377004) for crashing many tests with mozilla::net::nsHttpConnectionMgr::nsHalfOpenSocket::SetFastOpenConnected. r=backout on a CLOSED TREE

modules/libpref/init/all.js

@@ -4699,7 +4699,7 @@ pref("network.tcp.keepalive.retry_interval", 1); // seconds
 pref("network.tcp.keepalive.probe_count", 4);
 #endif
 
-pref("network.tcp.tcp_fastopen_enable", true);
+pref("network.tcp.tcp_fastopen_enable", false);
 pref("network.tcp.tcp_fastopen_consecutive_failure_limit", 5);
 
 // Whether to disable acceleration for all widgets.

netwerk/base/TCPFastOpenLayer.cpp

@@ -400,8 +400,8 @@ TCPFastOpenFinish(PRFileDesc *fd, PRErrorCode &err,
     // We have some data ready in the buffer we will send it with the syn
     // packet.
     PRInt32 rv = (tfoFd->lower->methods->sendto)(tfoFd->lower,
-                                                 nullptr,
-                                                 0,
+                                                 secret->mFirstPacketBuf,
+                                                 secret->mFirstPacketBufLen,
                                                  0, //flags
                                                  &secret->mAddr,
                                                  PR_INTERVAL_NO_WAIT);

netwerk/protocol/http/nsHttpConnectionMgr.cpp

@@ -4259,7 +4259,12 @@ nsHalfOpenSocket::SetFastOpenConnected(nsresult aError, bool aWillRetry)
         mStreamOut = nullptr;
         mStreamIn = nullptr;
 
-        Abandon();
+        // If backup transport ha already started put this HalfOpen back to
+        // mEnt list.
+        if (mBackupTransport) {
+            mEnt->mHalfOpens.AppendElement(this);
+            gHttpHandler->ConnMgr()->mNumHalfOpenConns++;
+        }
     }
 
     mFastOpenInProgress = false;