Switch the TCP reads on Windows to use non-blocking/non-async I/O.

chrome/common/chrome_switches.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/chrome_switches.h"
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 
 namespace switches {
@@ skipping 1522 matching lines @@
 const char kEnableSyncCredentialCaching[]    = "enable-sync-credential-caching";
 
 // For the DelegateExecute verb handler to launch Chrome in metro mode on
 // Windows 8 and higher.  Used when relaunching metro Chrome.
 const char kForceImmersive[]                 = "force-immersive";
 
 // For the DelegateExecute verb handler to launch Chrome in desktop mode on
 // Windows 8 and higher.  Used when relaunching metro Chrome.
 const char kForceDesktop[]                   = "force-desktop";
 
+// Allows for disabling the overlapped I/O for TCP reads.
+// Possible values are "on" or "off".
+// The default is "on" which matches the existing behavior.
+// "off" switches to use non-blocking reads and WSAEventSelect.
+const char kOverlappedRead[]                 = "overlapped-reads";
+
 // Relaunches metro Chrome on Windows 8 and higher using a given shortcut.
 const char kRelaunchShortcut[]               = "relaunch-shortcut";
 
 // Waits for the given handle to be signaled before relaunching metro Chrome on
 // Windows 8 and higher.
 const char kWaitForMutex[]                  = "wait-for-mutex";
 #endif
 
 #if defined(USE_AURA)
 // Opens an Ash window on startup.
@@ skipping 41 matching lines @@
   return true;
 #elif defined(OS_WIN)
   return true;
 #else
   return CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableFramelessConstrainedDialogs);
 #endif
 }
 
 }  // namespace chrome