Use a valid /prefetch argument when launching a process.

chrome/app/prefetch_argument_win.h

Index: chrome/app/prefetch_argument_win.h
diff --git a/chrome/app/prefetch_argument_win.h b/chrome/app/prefetch_argument_win.h
new file mode 100644
index 0000000000000000000000000000000000000000..acfaf218c686c0baba03355d4d1318ee0e1a1c93
--- /dev/null
+++ b/chrome/app/prefetch_argument_win.h
@@ -0,0 +1,15 @@
+// Copyright (c) 2016 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.
+
+#ifndef CHROME_APP_PREFETCH_ARGUMENT_WIN_H_
+#define CHROME_APP_PREFETCH_ARGUMENT_WIN_H_
+
+namespace base {
+class CommandLine;
+}  // namespace base
+
+// Returns true if |command_line| contains a valid /prefetch:# argument.
+bool HasValidWindowsPrefetchArgument(const base::CommandLine& command_line);
+
+#endif  // CHROME_APP_PREFETCH_ARGUMENT_WIN_H_