Use a valid /prefetch argument when launching a process.

components/nacl/browser/nacl_process_host.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 "components/nacl/browser/nacl_process_host.h"
 
 #include <string.h>
 #include <algorithm>
 #include <string>
 #include <utility>
@@ skipping 59 matching lines @@
 #include "content/public/browser/zygote_handle_linux.h"
 #include "ipc/ipc_channel_posix.h"
 #elif defined(OS_WIN)
 #include <windows.h>
 #include <winsock2.h>
 
 #include "base/threading/thread.h"
 #include "base/win/scoped_handle.h"
 #include "components/nacl/browser/nacl_broker_service_win.h"
 #include "components/nacl/common/nacl_debug_exception_handler_win.h"
+#include "components/startup_metric_utils/common/pre_read_field_trial_utils_win.h"
 #include "content/public/common/sandbox_init.h"
 #endif
 
 using content::BrowserThread;
 using content::ChildProcessData;
 using content::ChildProcessHost;
 using ppapi::proxy::SerializedHandle;
 
 namespace nacl {
 
@@ skipping 546 matching lines @@
   CopyNaClCommandLineArguments(cmd_line.get());
 
   cmd_line->AppendSwitchASCII(switches::kProcessType,
                               (uses_nonsfi_mode_ ?
                                switches::kNaClLoaderNonSfiProcess :
                                switches::kNaClLoaderProcess));
   cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id);
   if (NaClBrowser::GetDelegate()->DialogsAreSuppressed())
     cmd_line->AppendSwitch(switches::kNoErrorDialogs);
 
-  // On Windows we might need to start the broker process to launch a new loader
+#if defined(OS_WIN)
+  if (startup_metric_utils::GetPreReadOptions().use_prefetch_argument)
+    cmd_line->AppendArg(switches::kPrefetchArgumentOther);
+#endif  // defined(OS_WIN)
+
+// On Windows we might need to start the broker process to launch a new loader
 #if defined(OS_WIN)
   if (RunningOnWOW64()) {
     if (!NaClBrokerService::GetInstance()->LaunchLoader(
             weak_factory_.GetWeakPtr(), channel_id)) {
       SendErrorToRenderer("broker service did not launch process");
       return false;
     }
     return true;
   }
 #endif
@@ skipping 675 matching lines @@
     NaClStartDebugExceptionHandlerThread(
         process.Pass(), info, base::ThreadTaskRunnerHandle::Get(),
         base::Bind(&NaClProcessHost::OnDebugExceptionHandlerLaunchedByBroker,
                    weak_factory_.GetWeakPtr()));
     return true;
   }
 }
 #endif
 
 }  // namespace nacl