Use a valid /prefetch argument when launching a process.

content/public/common/content_switches.h

Index: content/public/common/content_switches.h
diff --git a/content/public/common/content_switches.h b/content/public/common/content_switches.h
index f22927cb3a0856d9ced5a8e7b0260294b98d4617..18248831abbcbb6ec9f75d7cef9d524f5b2f0ec8 100644
--- a/content/public/common/content_switches.h
+++ b/content/public/common/content_switches.h
@@ -289,6 +289,11 @@ extern const char kDisableThreadedEventHandlingMac[];
 #endif
 
 #if defined(OS_WIN)
+CONTENT_EXPORT extern const char kPrefetchArgumentRenderer[];
+CONTENT_EXPORT extern const char kPrefetchArgumentGpu[];
+CONTENT_EXPORT extern const char kPrefetchArgumentPpapi[];
+CONTENT_EXPORT extern const char kPrefetchArgumentPpapiBroker[];
+CONTENT_EXPORT extern const char kPrefetchArgumentOther[];
 // This switch contains the device scale factor passed to certain processes
 // like renderers, etc.
 CONTENT_EXPORT extern const char kDeviceScaleFactor[];